QSI 520c User guide

QSI 520c User guide
500 Series User Guide
Revision 1.9
September, 2010
Disclaimer:
The specifications in this document are subject to change without notice.
All trademarks mentioned in this document are the property of their respective owners,
and are used herein for informational purposes only.
 2007-2010 Quantum Scientific Imaging
Phone 888-QSI-4CCD • www.QSImaging.com
Table of Contents
1.
GETTING
STAR TED
Camera Selection
20
Status Indicators
21
What’s In the Box?
2
Imaging Options
22
Get to Know Your Camera
3
Other Options
22
Install Software and Drivers
4
Enable Pixel Masking
23
Confirm Installation and Camera Operation
4
Status and Notification
25
Launch MaxIm LE
4
Camera Status Indication
25
Connect the camera
5
Camera Error Indication
25
Take an image
7
Audible Beeper
27
View the image
8
Imaging Application Messages
27
2. CAMERA FEATUR E S
AND OPE RATION
Camera Attachment Options
3. CCD
9
IMAGING
OVERVIEW
How CCDs work
28
Using SLR Lenses
10
Types of CCDs
28
Attach the camera to your telescope
10
Full-Frame CCDs
28
Electrical Connections
11
Interline Transfer CCDs
29
DC Power Connector
11
Anti-Blooming CCDs
29
USB Connector
12
Microlenses
30
Guider Control Port
13
Single-shot color CCDs
30
Cooling the Camera
14
Signal versus noise
31
Standard Air Cooling
14
Reducing noise in CCD images
32
Liquid-Assisted Cooling
14
Dark Frames
32
How Much Cooling Is Enough
15
Flat Fields
34
Controlling the Cooler
16
Bias Frames
36
Internal Color Filter Wheel
18
Stacking Images
37
Advanced Setup Options
19
Color images
38
4. TAKING
5. GUIDING
IMAGES
Launch MaxIm LE
39
Autoguider support in MaxIm LE
65
Camera Control Window
40
Using an AutoGuider
66
Cool the CCD
42
Using a QSI 500 Series Camera as an
Focusing with MaxIm LE
43
AutoGuider
Take a single image
44
View the image in MaxIm LE
45
6.
Take a series of images
45
T-mount adapter
71
Image Calibration
47
2” nosepiece
71
Dark Frames
48
1 ¼” nosepiece
71
Bias Frames
48
C-mount adapter
71
Flat Fields
48
SLR lens adapter
72
Flat Darks
49
Liquid heat exchanger
72
Manual Image Calibration
49
Recirculating pump
72
Subtract Dark Frames
49
Color filter wheel
72
Scale by Flat Fields
51
Automatic Calibration in MaxIm LE
52
Calibrate Images in MaxIm LE
56
Combine Frames in MaxIm LE
57
Binning
60
Using the internal Color Filter Wheel
63
Shutting down your camera
64
Controlling with other software
64
69
ACCESS O RIES
7. CARE
&
MAINTEN ANCE
Cleaning the exterior
73
Installing or removing color filters
73
Installing or removing 31mm color filters 74
Cleaning the color filters
75
Cleaning the CCD cover glass
75
Updating the Firmware
75
Recharging the desiccant
77
Technical support
78
7.
APPENDI CES
Appendix A – 500 Series Specifications
79
Appendix B – Warranty
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1
Section
G U I D E
Getting Started
Thank you for your purchase of a QSI 500 Series Camera.
The QSI 500 Series family of thermoelectrically cooled CCD cameras is designed to
produce scientific-grade images with wide dynamic range, excellent linearity and low noise.
Your QSI 500 Series camera will provide years of service if properly treated and
maintained. To get the most from your camera, we recommend that you read this User
Guide thoroughly and follow the included precautions.
If you’re in a hurry to try out your new camera and are familiar with the general operation of
CCD cameras, this “Getting Started” section provides the basic information you will need to
setup your camera and take your first image. Please refer to the full User Guide and the
online help provided with MaxIm LE for complete instructions.
The QSI 500 Series Camera Family Showing Different Body Styles
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What’s In the Box?
Your QSI 500 Series camera was shipped in a water-tight Pelican case with custom-cut
foam to provide the ultimate in protection. Please take a few minutes to examine your
camera to make sure that it has arrived in good condition, and that the case contains the
items listed below. Note that additional items purchased at the time of order may be
included as well.
 Camera body
 Nosepiece
2” or 1 ¼” depending on configuration
 Mounting Adapter
T-Mount or C-Mount depending on configuration
 Body cap
T-Mount or C-Mount depending on configuration
 AC Power Adapter
Universal AC power supply (100-240VAC, 50-60Hz) with
detachable, region-specific AC power cord
 USB Cable
10 ft. USB 2.0 cable
 Guider Cable
10 ft. guider cable with modular connectors on each end
 Tools
Tool kit for camera maintenance
 Documentation envelope containing the following:



Quick Start Guide
CD-ROM containing the Installation program, MaxIm LE, the USB and
camera drivers, and the Installation Guide and this User Guide in PDF format.
(Optional) A document with the license information for any licensed software,
such as MaxIm LE or MaxIm DL.
Open Pelican case showing QSI 500 Series camera and standard accessories
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Get to Know Your Camera
Take a few minutes to familiarize yourself with the external
connections and features of your camera.
The image above shows the major external features of a typical QSI 500 Series camera.
The depth of the Camera Cover on your camera may differ depending on the internal
options installed. See the “QSI 500 Series WSG User Guide Supplement” for additional
details on WSG models with the Integrated Guider Port.
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Install Software and Drivers
The USB drivers and associated software included on the installation CD-ROM must be
installed before connecting your QSI camera to your computer.
Note: Do not connect your camera to your computer until instructed to do so
during the camera installation process.
Refer to the QSI 500 Series Camera Installation Guide for complete software and
hardware installation instructions.
Confirm Installation and Camera Operation
After the successful installation of the camera and the associated software is complete, you
can quickly test your camera with MaxIm LE or your software application of choice. Leave
the camera USB cable and power supply connected, and follow the steps below.
Launch MaxIm LE (if purchased with your camera)
After installing the camera drivers and MaxIm LE from the Installation CD-ROM, launch
MaxIm LE by double-clicking the MaxIm LE icon on your desktop or by selecting
“Programs > MaxIm LE > MaxIm LE” from the Windows Start menu.
The first time you run MaxIm LE you will be asked to enter your temporary User
Registration information. Enter the Name, Email, Expiry dates and Serial number
information exactly as printed on the MaxIm LE License Information sheet included in the
documentation envelope with your camera.
Caution: Do not enter your real name and email address. Enter the information
exactly as printed on the included MaxIm LE License Information sheet.
This license will work for 30 days from the time it is installed. You must register directly
with Diffraction Limited to receive your permanent license. Select Register Online
from the Help Menu in MaxIm LE and follow the directions to receive your permanent
license.
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Connect the camera
Select “Camera Control Window” from the View menu to open the Camera Control
Window.
MaxIm will open the Camera Control window and display the Setup tab. After MaxIm is
installed it must be told which camera to use.
Click the “Setup” button in the upper left corner under Main CCD Camera.
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Select “QSI Universal” from the Camera Model list box. Click OK.
That will take you back to the Camera Control Window. If you have a QSI camera with an
internal color filter wheel you’ll also need to tell MaxIm about that by clicking “Setup” under
“Filter Wheel” toward the upper right of the Setup tab.
Select “QSI Universal” as the filter wheel model. Click OK.
Note:
The filter wheel must be setup separately from the camera even on 500
Series WS and WSG model cameras where the filter wheel is integral to the
camera.
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Click the “Connect” button to establish communication between MaxIm and your QSI
camera. If MaxIm fails to connect to the camera, double-check that power is supplied to the
camera and that the USB cable is securely connected. Once MaxIm connects to the
camera the Camera Control window will look like this:
Note:
This example assumes the camera does not have a color filter wheel. If
you setup a filter wheel, “QSI Universal” will be displayed under Filter Wheel in
the dialog above.
Take an image
Click the “Expose” tab along the top of the Camera Control window.
There are several fields and buttons in this window. On the left is a series of radio buttons
to select the type of frame to expose. The options are Light, Bias, Dark and Flat. Click the
button next to “Bias” to select a bias frame. A bias frame is an exposure with the shutter
closed of essentially zero exposure time. The Minutes and Seconds will be grayed
indicating that the exposure time can’t be modified for a bias frame. Make sure the Delay is
set to “0”. Click “Expose” to take one bias frame.
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View the image
MaxIm will instruct the camera to acquire a bias frame and then automatically download
and display the resulting image. Your screen should look something like this.
Your display may vary somewhat from the screen shot above and the image displayed may
be larger or smaller than that shown depending on your camera model. While a room
temperature Bias image isn't very exciting, this does provide confirmation that your software
and camera are installed and working properly.
Congratulations, you have just connected your new QSI 500 Series camera and
acquired your first image. If you’re familiar with MaxIm LE or MaxIm DL, or are
using some other camera control software such as CCDSoft from Software
Bisque, you are now ready to begin taking additional images.
For all users, but especially if you’re new to CCD imaging with MaxIm LE, we
suggest you read the entire QSI 500 Series Camera User Guide to familiarize
yourself with all of the features and capabilities of your new QSI camera.
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2
Section
G U I D E
Camera Features and Operation
Camera Attachment Options
The camera can be attached to your telescope or lens in a variety of ways. The image
above shows the industry standard T-Adapter with an attached 2" nosepiece. An optional
1.25" nosepiece is also available. The T-Adapter is compatible with a wide variety of
standard accessories. A larger diameter 2.156” adapter is available for WSG models.
An optional C-Adapter adapter is also available. The C-Adapter replaces the T-Adapter and
is compatible with many standard lenses, lens mounting accessories and other equipment
such as microscopes.
Note:
The T-Adapter has industry standard 42mm diameter x 0.75mm pitch
threads. The C-Adapter has industry standard 1" x 32TPI threads. Always make
certain that any device you attempt to thread into either adapter has proper
matching threads. Some optical components have threads that look like they
might work, but have slightly different dimensions. Never force-thread
anything into the adapters.
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Using SLR Lenses
The C-Adapter and T-adapter can be used to attach
many standard SLR lens attached to your camera.
The image at the right shows an Olympus OM series
SLR lens attached to a QSI Model 520i camera.
Optional SLR lens adapters are available to fit a
variety of popular SLR camera lenses. See Section 6
in this Guide for a list of available adapters and
compatibility requirements.
Note:
Custom mounting adapters can be employed to satisfy many unique or
non-standard mounting requirements. Contact QSI for the dimensions and
requirements for custom mounting adapters.
Attach the camera to your telescope
The picture below shows a QSI 500 Series camera with 2" nosepiece being fitted to the 2"
focusing tube of a refracting telescope. Always use the largest nosepiece that your
telescope will allow to minimize any vignetting of your image.
With the correct diameter nosepiece firmly screwed in to the front of the camera, carefully
guide the nosepiece into the eyepiece adapter on your telescope. Tighten any retaining
screw or screws to ensure the camera is stable and will not slip or move when the
orientation of the telescope changes.
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Electrical Connections
The image at the left is a closeup of the bottom of the camera
body. All electrical connections to
the camera are made through the
three connectors located on this
connector panel. The panel is
recessed into the camera body to
protect the connectors when no
cables are attached.
DC Power Connector
The camera is ordinarily powered by the included AC power adapter which plugs into the
middle connector on the bottom of the camera. The AC power adapter accepts any input
voltage from 90v to 240v and 50-60 Hz. It is supplied with a region-specific AC power cord.
Shortly after power is applied to the camera, the Camera Status Indicator on the back of the
camera will start glowing yellow indicating that the camera is starting up. The camera will
make a small “chirp” sound and then a few seconds later will make a “chirp chirp” sound
indicating that the camera successfully completed its initialization steps. The Camera
Status Indicator will begin flashing green if the camera is not connected via the USB cable.
The Camera Status Indicator will glow solid green once the camera is connected to the
computer via the USB cable. See the Status and Notification discussion later in this
Section for additional detail.
Note:
Power-up initialization can take up to 6 seconds. It is not possible to
connect to the camera from the imaging application (MaxIm LE, CCDSoft, etc.)
during this time. Any attempt to do so will cause an error message to be displayed
by your imaging application.
Note: The camera is designed to operate on stable, regulated 12V DC power and
consumes less than 2 amps at full power. DC power input above or below 12V
will decrease the maximum cooling capability of the camera by increasing power
dissipation or lowering cooling efficiency. If the input voltage is below 11V or
above 14V the camera will report an error until the voltage is returned to the
specified range. See Status and Notification below.
Caution: Applying an input voltage over 16V or under 10V may
permanently damage the camera and will void the camera warranty.
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Note:
The camera power connecter uses a standard 2.1mm coaxial DC power
connector with center positive. Inside diameter 2.1mm, outside diameter 5.5mm,
length 10mm.
Caution:
Because of the wide range of potential power sources (especially with
field operations that can also employ batteries, generators, DC inverters, etc.)
there is the real possibility of damaging your camera and other electrical
equipment by creating unexpected ground loops and different ground reference
potentials between your equipment.
It is highly recommended that the included AC adapter be used to power the
camera at all times. If a power source other than the included AC adapter is used,
it is your responsibly to insure that it is suitable. Avoid sharing the camera DC
power source with other devices that can produce excessive noise (old technology
dew heaters, etc.) and possible ground loops that could interfere with the reliable
operation, or even damage your imaging equipment.
If you choose to use a power source other than the included AC adapter and are
uncertain about meeting these requirements, please contact QSI for assistance.
USB Connector
The camera's USB interface is compatible with USB 2.0 and 1.1. The included USB 2.0
cable plugs into the USB port on the camera connector panel. The other side connects to
any standard USB port on your computer. All camera control commands and resulting
images are passed over the USB cable.
Note: Do not connect your camera to your computer unless you have
successfully installed the camera software and drivers.
After the camera power-up initialization is complete, and the camera's USB cable is
connected to your computer, the computer will make a Plug-N-Play sound indicating that a
device was connected to the computer. This means that your camera is ready and is
listening for commands to be sent over the USB connection.
Note:
QSI 500 Series cameras do not draw power from the USB bus. Powered
hubs are not necessary for operation.
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Guider Control Port
All QSI 500 Series cameras have a Guider Control Port that can be used in conjunction with
MaxIm LE (or other CCD imaging software) to 'guide' your telescope mount for longduration astro-imaging. Ordinarily, the Port is only operational if the camera is being used as
the 'Guider' camera, or if you’re using the QSI camera as your main imaging camera and
have configured MaxIm to send guider correction signals through the ”Main Relays”. See
MaxIm online help for details.
The Guider Port employs an RJ-25, 6-conductor modular connector. The interface scheme
is compatible with most modern telescope mounts. Typically, a 6P6C (6 position, 6
conductor) telephone-type cable is required for connecting the camera to the mount's guider
input. This type of cable is commonly available at retailers such as Radio Shack. A 10 ft.
version of this cable is supplied with 500 Series cameras.
The image below summarizes how the Guider Port and compatible cable are wired:
Note: The Guider Port outputs employ optically isolated solid-state switches that
mimic the traditional behavior of older technology mechanical relays. The optical
isolation prevents potentially interfering or damaging ground loops between the
camera and mount.
This newer approach is compatible with most modern telescope mounts (Meade,
Losmandy, Software Bisque, etc.) that employ logic inputs pulled to VCC with a
suitable load resistor.
Adapter cables are available from third parties to connect to other guider port
configurations, such as the Mini-DIN connector on Takahashi mounts.
Caution:
Do not apply more than 50v or 50ma to the guider port pins. The
'Common' input must be at ground, or zero volt potential relative to the control
inputs of your mount. Contact QSI if you are uncertain about your mount's
electrical characteristics.
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Cooling the Camera
Cooling the CCD is essential for successful astro-imaging. Cooling dramatically reduces the
dark current and resulting thermal noise in an image and makes long exposures practical.
See the discussion in the 'CCD Imaging Overview' Section on dark current and noise.
QSI 500 Series cameras use a very efficient thermo-electric cooler (TEC) which relies on
the 'Peltier Effect' to cool the CCD. When power is applied to a TEC, one side of the device
gets cold and other side gets hot, essentially pumping heat from the cold side to the hot
side. All QSI 500 Series cameras employ a two-stage TEC to increase the differential
cooling effect.
The more power applied to the TEC, the greater the differential cooling and the colder the
CCD can get. The heat pumped from the CCD, as well as the power dissipated by the TEC,
creates a significant amount of excess heat that must be removed from the camera. QSI
500 Series cameras employ two different methods for removing this heat.
Standard Air Cooling
The back of a QSI 500 Series camera acts as a large heatsink with cooling fins machined
directly into the body. Two automatically controlled cooling fans force air through these fins.
The movement of air through the cooling fins greatly increases the amount of heat removed
from the camera.
Keep in mind that the lowest temperature that the CCD can be cooled is limited by the
ambient air temperature and the speed of the cooling fans. Achieving very low temperatures
is easy when imaging outdoors during cooler weather. If it is particularly cold you may not
even need to turn the fans on. If the weather is warm and humid you may not be able to
cool the CCD to the desired temperature. See the specifications for your camera to
determine the maximum cooling differential you can expect under typical conditions.
Liquid-Assisted Cooling
Forced air cooling is usually all that is
needed to reach normal levels of cooling.
However, in warm weather or particularly
demanding situations, additional cooling can
be achieved with the optional Liquid Heat
Exchanger, or LHX. The LHX utilizes
recirculating water for more efficient removal
of heat from the camera. All things being
equal, the LHX can provide an additional 7ºC
to 10ºC of CCD cooling. It attaches to the
rear of the camera body as illustrated in the
image to the right. The LHX includes a thin
thermal pad. Place the thermal pad between
the LHX and the camera body. Hold the
LHX and pad in place with the provided
screws.
Water flows through the two hoses, colored
blue in this picture. Self-sealing quick-disconnect couplings are used to attach the hoses to
the LHX so that the hoses can be removed easily without leakage of the recirculating water.
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There are numerous ways of supplying recirculating water for the camera. One of the
simpler and more common methods for astro-photography is to place a small submersible
pump into a 5 gallon plastic pail full of cool water. The temperature of this amount of water
will rise by only a few degrees after a full night of imaging. For additional details on the
Liquid Heat Exchanger, see the Accessories section below.
Note:
The Fans can usually be turned off when using the LHX. In fact, the fans
may actually decrease the cooling ability if the air is warmer than the liquid.
Caution:
It is generally advised that only water be used in the LHX. Coolants
such as ethylene glycol and some solvents may damage the seals and gaskets.
Additional cooling tips can be found in the QSI Knowledge base on the QSI web site:
http://store.qsimaging.com/kb_results.asp?ID=6
How Much Cooling Is Enough
Good results can be obtained with the CCD cooled to -10ºC when taking modest length
exposures. This is easy to achieve with forced air cooling when the ambient air is at 25ºC
(77ºF). For most CCDs used in QSI 500 Series cameras, dark current is reduced by half for
every 6ºC drop in the temperature of the CCD. Cooling from 26C to -10ºC results in a 64fold decrease in CCD dark current. For more demanding imaging and longer exposures,
lower temperatures are desirable. Cooling the CCD another 12ºC to -22ºC lowers the dark
current further to just 0.4% of the dark current at 26C. Cooling below -30ºC results in a
diminishing improvement as the noise from the dark current is outweighed by the intrinsic
read noise of the CCD itself. The camera will actively prevent the CCD from being cooled
below -40ºC.
Fahrenheit
Celsius
-40F
-40C
-20F
-29C
0F
-18C
20F
-7C
32F
0C
40F
4C
60F
16C
80F
27C
Note:
Refer to the specification sheets at the end of this Guide for the exact
cooling specifications for your particular camera model. Keep in mind that
ambient temperature changes, air movement, and even relative humidity can
affect the temperature that the camera can reach and maintain.
Note:
The cooler is not designed to raise the temperature of the CCD above the
temperature of the camera body, i.e. it can not heat the CCD. If the ambient
temperature is -10ºC, the cooler can not bring the CCD temperature up to 0ºC.
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When using forced-air cooling the body of the camera and the window of the CCD chamber
can be up to 12ºC warmer than the surrounding ambient air temperature. By definition, the
camera will be above the dew point (or frost point) and condensation will not form. When
using the LHX there is the opportunity to drive the enclosure of the camera and the CCD
chamber window significantly below ambient temperature if the recirculating water is colder
that the surrounding environment. If the relative humidity is high enough, this action could
drop the camera below the dew/frost point and condensation will form.
Caution:
Do not allow excessive dew or frost to collect in or on the camera.
Exercise the normal precautions that you would with any precision optical or
electronic device. Never use the LHX to drive the camera temperature so low that
liquid water forms on or in the camera. Under certain conditions excessive
moisture can impair or damage the optical coatings and the internal electronics.
Controlling the Cooler
The operation of the cooler is managed from your CCD imaging application (MaxIm,
CCDSoft, etc.) When power is first applied to your camera the cooler is in an inactive state.
It must be actively turned on. The following explores the technical details of camera cooling
utilizing MaxIm as the imaging application. For step-by-step operating instructions and
changing the CCD setpoint temperature, see Section 4.
Below is a snapshot of the Setup tab in the Camera Control window, just after the Connect
and then Cooler On button was clicked. Notice that the current CCD temperature is 23ºC,
the default Setpoint is 0ºC, and that the cooler power is 100%
When the Cooler On button is clicked, the camera immediately starts cooling the CCD at full
power. The cooler will stay at full power until it has cooled the CCD to within a few degrees
of the setpoint temperature. The camera will then start adjusting the power applied to the
cooler as it approaches the setpoint temperature. The displayed CCD temperature may
slightly over-shoot the setpoint temperature as the regulation servo locks. It can take a
couple more minutes for the temperature servo to achieve a solid lock. After lock is
achieved, the camera will keep the CCD temperature within 0.1ºC of the setpoint.
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The following is an image of the same Camera Control window 5 minutes after clicking the
Cooler On button. Notice that the CCD temperature is now being regulated at 0ºC and that
the power level has settled down to a modest 40%.
Note:
Depending on the ambient temperature and Cooler setpoint, the time to
reach the setpoint temperature can take as long as 15 minutes. Once the CCD
temperature has stabilized at the setpoint value, it is recommended to allow the
entire camera an additional 5 to 10 minutes to reach thermal equilibrium.
Note:
Best regulation is achieved when the power to the cooler is kept below
85%. This gives the camera some headroom to compensate for variations in the
ambient temperature. If the camera can not reach the desired temperature, it will
keep trying by running the cooler at 100% power indefinitely. If the desired
temperature hasn’t been reached within 15-20 minutes, or the power level is
above 85%, we recommend selecting a higher Setpoint temperature.
Caution:
Be careful not to block free air movement around the camera, or any
air flow through the fans and cooling fins on the rear of the camera.
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Internal Color Filter Wheel
A five position filter wheel is available for some models of QSI 500 Series cameras. The
filter wheel is designed to hold five standard 1.25" filters, and on some models, optional
unmounted 31mm filters. The following image shows filter positions 1-4 occupied by red,
green, blue and luminance filters respectively. Those are the standard filter positions if your
camera was configured at the factory with LRGB filters.
Note the reflection of the complementary colors
with this set of LRGB dichroic filters.
Note: QSI offers LRGB filter sets from a number of respected manufacturers, as
well as other specialized filters for astronomical imaging. Alternatives can be
specified at the time of order.
The filter wheel is designed to be removed and replaced easily. After detaching the camera
cover, the filter wheel can be removed by loosening a single shoulder screw. This allows the
user to have additional filter wheels populated with different combinations of filters and
interchange them quickly while operating in the field. See the Care and Maintenance
section for details.
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Advanced Setup Options
The QSI Configuration dialog box is used to view or change camera settings that are
seldom modified. Bring up the Camera Control dialog box and click the Setup tab. The
camera must be disconnected to proceed further. If necessary, click the Disconnect button.
Click the Setup button in the upper left corner under “Main CCD Camera” to open the Setup
QSI Universal dialog box for the Main camera. If the Camera Model list box does not
indicate QSI Universal, select it now.
Click the Advanced button. The "QSI Configuration - Main Camera" window will appear as
illustrated in the following image.
Note:
If you are also using a QSI camera as an Autoguider, you can navigate to a
similar window entitled "QSI Configuration - Guider Camera" by clicking the
Setup button in the Autoguider field of the Camera Control window. The steps
for configuring the Guider camera are identical to those for the Main camera.
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Note:
The very first time a QSI camera is connected to the computer it will set
the relevant options shown above to default values based on the configuration of
the specific camera. From that point forward, the settings are maintained in the
Windows Registry. All subsequent changes are made to these Registry settings.
This allows the computer to always know your last selections for each camera and
restore them the next time you begin imaging. Also, a camera's settings are
remembered uniquely when being used as a Main camera and when being used as
a Guider camera.
Only those settings that are relevant to a particular camera model and software package
are enabled. Options that don't apply are grayed-out.
Camera Selection
USB Interface
Select the specific QSI camera that you wish to control from
those listed in the USB Interface list box. Cameras are
tracked by their serial number. That is the number located in
parenthesis, and will match the number engraved on the
camera nameplate / desiccant cover.
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If a camera has previously been assigned to another role, it
will not appear in the list. For example, if a camera is currently
assigned as the Main camera, it will not appear as an option
in the Guider selection list box.
Ethernet Interface
Disabled on QSI 500 Series cameras
Note:
If only one camera is connected to the computer, the computer will
always select that camera by default. You do not need to make the selection here.
If two or more cameras are available and they match the serial numbers of the last
camera(s) used for the Main and/or Guider camera, the computer will
automatically reconnect to them in the same roles.
The only time you need to actively make a selection is when you have two or
more cameras available and you want to:
1) Change the camera roles or
2) Select a new camera that has never been connected to this computer before.
Status Indicators
LED Indicator On
Uncheck to disable the Status Indicator LED on the back of
the camera. Only normal status indications are disabled.
Visual indication of errors can not be disabled.
Sound On
Uncheck to disable the Audible Beeper. Sounds associated
with camera initialization and error notification can not be
disabled.
Fan Mode
Can be set to Off, Quiet or Full-Speed. Quiet is the default
setting and is sufficient in most situations.
If Off is selected the fans are disabled unless the camera
temperature begins to exceed a predefined safe level. At that
point the fans are turned on and run at full speed until the
camera temperature is reduced to a safe level. Turning the
fans off is only recommended when there is an alternate
source of cooling such as an external fan or the when
using the Liquid Heat Exchanger.
When in Quiet mode the camera runs the fans at reduced
speed for quieter operation. If more cooling is required to
maintain the setpoint temperature, the fan speed is increased
as needed to maintain the desired temperature.
Full-Speed mode runs the fans at full speed.
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Imaging Options
Camera Gain
Default setting is “High”. This setting can only be changed on
cameras that support switchable gain. With supported
cameras, gain can be set to “Low” in order to utilize the full
dynamic range of the CCD when using on-chip binning.
“High” gain is generally used for 1x1 binning. “Low” binning is
recommended for binning settings other than 1x1.
Shutter Priority
Settings are “Mechanical” or “Electronic”. This setting can
only be changed on cameras with interline transfer CCDs
such as the QSI 520 or 540. In “Mechanical” priority the
shutter is closed after each exposure. In “Electronic” priority
the mechanical shutter is left open unless the camera is
exposing a dark or bias frame. Electronic priority provides
the highest possible frame rate when taking short exposures.
Anti-Blooming
Default setting is “Off”. This can only be set to On with
cameras that have CCDs with anti-blooming protection that
can be controlled or adjusted electronically.
Pre-Exposure Flush This number determines how aggressively the pixels in the
CCD are flushed between exposures. The default value is
“normal”. It can be lowered to decrease the time between
exposures or increased if you want to ensure that the CCD
retains less stray charge between exposures.
When using full-frame CCDs such as in the QSI 504, 516 and
532, the Flush options correspond to 0, 1, 2, 4, and 8 flush
cycles respectively. With interline transfer CCDs a variety of
flushing techniques are used by the different Flush options to
provide increasingly aggressive flushing of stray charge
before beginning an exposure.
Show D/L Progress Check this box to enable reporting progress while an image is
being downloaded from the camera. The default setting is
“Off”. If Show D/L Progress is enabled it will modestly
increase the download time.
Optimization
This setting is disabled on QSI 500 Series cameras. 500
Series cameras always optimize for image quality.
Other Options
Cooling Control and Filter Wheel in the Advanced Dialog Box will only be enabled when
using Software packages that do not offer direct control of these features from within the
application. If the options are grayed out you should change these settings using the
features built into the application. Refer to the User Guide for your camera control
application for details.
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Cooling Control
For camera control applications that do not provide a way to
enable cooling or control the set point temperature, cooling
can be turned on by clicking the checkbox next to “Cooler
On.” The desired temperature can then be set in the text box
in degrees Celsius.
Filter Wheel
For camera control applications that do not provide a way to
setup and/or control the filter wheel, click the “Setup…” button
to assign names to the filter positions of your camera.
Enable Pixel Masking
Enable Pixel Masking is an advanced function that does not need to be used under most
normal circumstances. Click the “Enable Pixel Masking” checkbox to expose a table of
pixel X, Y values (see dialog box below) Enter the X,Y coordinates of a pixel that you wish
to be “masked” or ignored.
When a pixel value is “masked” its original value is replaced with a constant, typically 200.
It can be used to replace the value of excessively bright or dark pixels with a known value.
This function can sometimes be handy, for instance, when using guiding or focusing
software the automatically selects the brightest pixel in the image. If the brightest pixel is a
hot pixel rather than a star, then masking the pixel will allow the software to function
correctly.
Some camera control applications offer more sophisticated methods of interpolating missing
values from the values of surrounding pixels. See your software’s User Guide for additional
details.
Click “Add Pixel” to add another entry in the Mask Pixels table. If a pixel entry is selected,
the new entry will be entered above the current entry. If no pixel is selected, a new entry will
be added at the end of the table.
Select a pixel X or Y value and click “Delete Pixel” to delete that pixel value from the Mask
Pixels table.
Note:
Pixel values are stored by camera serial number in the registry of the
connected computer. If you have multiple QSI cameras, separate “Mask Pixel”
tables will be automatically maintained for each camera.
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Advanced Dialog box showing the “Mask Pixels” table
The current camera status is shown in the text field to the left of the OK and Cancel buttons.
Click the OK button to save your changes or the Cancel button to abort them. This will
return you to the Setup QSI Universal window. Click OK again and you'll be returned to the
Setup tab in the Camera Control window.
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Status and Notification
QSI 500 Series camera utilizes a variety of methods to inform the operator of the camera's
operation, status and other events. A built-in LED Status Indicator and audible Beeper
provide notification at the camera. In the event of a serious internal error, the camera will
also pass a descriptive error code back to the controlling application which then reports it to
the user.
Camera Status Indication
There is a small tri-state LED indicator on the camera back just above the connector panel.
The LED indicates the current status of the camera and any operation that is underway.
The LED can display green, yellow or red and flash at various rates.
Camera Operational State Indication
Green solid
In Idle state, not Busy. Ready to accept commands.
Green flashing
USB cable not connected. Not ready to accept commands.
This only indicates that the USB cable is not physically
connected between the camera and computer or hub.
Yellow solid
Busy with internal operation. Not ready to accept commands.
This state is seen while the camera is performing power-up
initialization, moving the filter wheel or shutter, or when
uploading an image to the computer
Yellow flashing
Upgrading firmware. The indicator will flash rapidly while
downloading the camera firmware and then more slowly as it
is validated.
Red slow flashing Exposing an image. Flashes once every 4 seconds. The
camera can still respond to commands (such as abort image
or read CCD temperature) while in this state.
Note:
The Status Indicator can be disabled for the normal camera states
described above. This may be desirable during long exposures where the light
from the Status Indicator may be reflected into the telescope. See the Advanced
Setup dialog box.
Camera Error Indication
Camera error conditions are indicated by a more elaborate sequence of Red and Yellow
flashes of the Status Indicator. Errors are classified as Soft errors or Hard errors. Soft errors
are those that the camera can mitigate, but typically need operator action to resolve. Soft
errors always begin with one Red flash followed by a number of Yellow flashes.
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Camera Soft Error State Indication
Flash Red:
1
Flash Yellow:
1
Flash Red:
1
Flash Yellow:
2
Flash Red:
1
Flash Yellow:
3
Flash Red:
1
Flash Yellow:
4
Flash Red:
1
Flash Yellow:
5
Flash Red:
1
Flash Yellow:
6
The camera is over-temperature. Camera has exceeded the
40°C maximum recommended operating temperature for the
internal electronics and enclosure. This sequence will repeat
every four seconds as long as the camera remains “overtemperature”.
The CCD is under-temperature. The CCD has exceeded the
-40°C minimum recommended operating temperature. This
sequence will repeat every four seconds as long as the CCD
remains “under-temperature”.
The camera DC supply voltage is below the 11V minimum
recommended operating level. This sequence will repeat
every four seconds until the supply voltage is raised above
this threshold.
The camera DC supply voltage is above the 14V maximum
recommended operating level. This sequence will repeat
every four seconds until the supply voltage is lowered below
this threshold.
The filter wheel has encountered a problem and is no longer
operational. The camera will still function, but will no longer
attempt to move the filter wheel. The filter wheel may be in
any position. Power to the camera must be turned off and on
to reinitialize the filter wheel.
The shutter has encountered a problem and is no longer
operational. The camera will still function, but will no longer
attempt to operate the shutter. The shutter may be in any
state. Power to the camera must be turned off and on to
reinitialize the shutter.
Hard errors occur when the USB communication channel to the computer malfunctions or
the camera has an unrecoverable internal error. The power to the camera must be turned
off and on to reinitialize the camera and USB connection to the computer. This class of error
is generally caused by problems with the USB connection between the camera and
computer or software and firmware version incompatibility. Hard errors always begin with
two Red flashes followed by a number of Yellow flashes.
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Camera Hard Error State Indication
Flash Red:
2
Flash Yellow:
N
The number of yellow flashes of the Status Indicator specifies
the nature of the camera Hard Error. This code indicates the
technical nature of the problem.
Note:
Neither class of error indications can be disabled with the Advanced
Dialog box. If you encounter any of these errors, make a record of the code
flashed by the Status Indicator. This information will be useful if you need to
contact QSI Customer Service.
Audible Beeper
There is a small beeper located inside the camera that is used to provide notification of
various events. Shortly after power is applied to the camera, the Beeper will make a short
“chirp” sound indicating that the camera is entering the Initialization mode. Once the camera
is fully operational the Beeper will make a “chirp-chirp” sound. At this point the camera is
ready to communicate over the USB connection to the computer.
The Beeper is also sounded in sequence with the Status Indicator when any sort of error
occurs. A long beep is sounded whenever the Status Indicator is displaying Red and a short
beep when displaying yellow. This audible alert is intended to alert the operator in case the
Status Indicator is not noticed or not visible.
Note: The Beeper disable function in the Advanced Dialog box does not apply to
power-on initialization or error notifications. These events are always
accompanied by the corresponding audible beeper sounds.
Imaging Application Messages
The imaging applications (MaxIm LE, MaxIm DL, CCDSoft, etc.) can display messages in
response to activities performed with the camera. Many of these messages have
straightforward text descriptions of the event. Others messages may include only a numeric
code. If you get a message indicating an error, record the text message or numeric code in
the event that you need to contact QSI Customer Support.
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3
Section
G U I D E
CCD Imaging Overview
This section is intended only as a brief overview of CCDs and CCD Imaging. If you are new
to CCD imaging there are a number of excellent books that you can use to gain a deeper
understanding of the issues and techniques. Two very well regarded books that we
recommend are:

The New CCD Astronomy by Ron Wodaski

The Handbook of Astronomical Image Processing by Richard Berry and Jim Burnell
How CCDs work
Charge Coupled Devices (CCD) work by converting photons into electrons which are then
stored in individual pixels. A CCD is organized in a two-dimensional array of pixels. The
CCDs used in the QSI 500 Series cameras at the time of printing range from roughly
400,000 pixels (768W x 512H) to 8.3 million pixels (3326W x 2504H).
Each pixel can hold some maximum number of electrons. CCDs currently used in the QSI
500 Series can hold from 25,500 to as many as 100,000 electrons depending on the
specific model of CCD. While integrating (exposing) an image, photons strike individual
pixels and are converted to electrons and stored in each pixel well. The effectiveness of
this process is referred to as Quantum Efficiency (QE). The number of electrons stored in
each pixel “well” is proportional to the number of photons that struck that pixel. This linear
response is one of the key traits that make CCDs exceptionally well suited to astronomical
imaging. A subject that is twice as bright will build up twice as many electrons in the CCD.
After an exposure is complete, the electrons in each pixel are shifted out of the CCD and
converted to a number, indicating how dark or light each particular pixel was. Those
brightness values for each pixel are then stored in the image file, typically a FITS file for
astronomical imaging.
Types of CCDs
CCDs are available in a variety of designs and technologies. QSI 500 Series cameras
currently employ two different types of CCDs, Full Frame and Interline Transfer, with
numerous optional features.
Full-Frame CCDs
Full-Frame CCDs generally provide the highest sensitivity and the widest linear response
range of these two types of CCDs. These characteristics make full-frame CCDs ideally
suited to astronomical imaging. Full-frame CCDs must employ a mechanical shutter to
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prevent light from falling on the CCD surface while the image is being shifted out of the
CCD.
Interline Transfer CCDs
Interline transfer CCDs work somewhat differently. In an interline transfer CCD, next to
every column of pixels is a specialized storage column that is covered by a mask to prevent
light from hitting the storage 'pixels' underneath. When an exposure is complete, the entire
image is shifted in a single operation into this masked storage column. The pixels which
are now under the mask stop building additional charge and are shifted out of the CCD in
the same fashion as a full-frame CCD. Interline transfer CCDs give up some sensitivity
because a sizable portion of the potential light gathering surface of the CCD is occupied by
the masked storage columns. The key benefit of interline transfer CCDs is that the shifting
of the image into the masked storage column acts like a very precise electronic shutter
allowing short, accurate exposures.
Anti-Blooming CCDs
CCDs are subject to an electronic artifact called “blooming” that results in bright vertical
streaks leading from bright objects.
The 60-second image above shows a portion of M42, the great nebula in Orion. The stars that make up the center of
the nebula are much brighter than the surrounding nebula. Taking an exposure long enough to show detail in the
nebula causes the bright stars to bloom. Note that some of the other brighter stars around the image also show
varying amounts of blooming.
Blooming occurs when taking images of bright objects because when a pixel reaches its full
well capacity, say 100,000 electrons, the electrons literally overflow into adjoining pixels
eventually causing them to fill and overflow as well. In a severely bloomed image, the bright
blooming trail can lead all the way to the edge of the image. Data under a “bloom” is lost
although there are a variety of processing techniques that can be used to hide pixel blooms
in a final processed image.
Anti-blooming is a feature available on many full-frame and most interline transfer CCDs.
Anti-blooming technology limits the number of electrons that can accumulate in a pixel by
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draining off excess electrons before they exceed the capacity of the pixel. This can increase
the dynamic rage of the CCD by as much as 300 times or more. This increase in dynamic
range greatly reduces the difficulty of imaging bright objects.
Anti-blooming CCDs make astrophotography more convenient, but with tradeoffs in
quantum efficiency (QE) and linearity. Anti-blooming protection requires additional circuitry
on the surface of the CCD, reducing the physical size and consequently the light gathering
area of each pixel. Anti-blooming CCDs also have a non-linear response to light. This nonlinearity becomes significant as a pixel fills beyond 50%. The closer a pixel gets to full-well
capacity, the greater the rate of electron drainage in order to prevent blooming. This
generally isn’t a problem if your goal is producing great-looking pictures of the night sky, but
anti-blooming CCDs are generally not appropriate for photometric and other scientific use
where accurately recording the relative brightness of objects is important.
Microlenses
CCDs only record the light that hits the photosensitive portion of the CCD. Most CCDs are
“front illuminated” meaning that the light strikes the top surface of the integrated circuit
forming the CCD. A portion of the surface of the CCD is covered with the electronic circuits
that make a CCD work. Light striking a part of the CCD covered by a circuit will not get
recorded by the CCD.
The surface of some CCDs is covered with microlenses which focus more of the light
striking the surface of the CCD onto the photosensitive area away from the circuits.
The amount of the CCD surface covered in circuits is one factor in determining the quantum
efficiency (QE) of the CCD. QE is a measure of how efficiently the CCD converts photons
striking the CCD into electrons stored in any given pixel. QE varies by type of CCD and by
the wavelength of light. Adding microlenses to a front-illuminated CCD will raise the
quantum efficiency of the CCD. Typical peak QE values for the CCDs used in QSI 500
Series cameras range from 35% to over 80%. Microlens models tend to have the highest
QE, while anti-blooming gate models tend to have the lowest QE. Here is a graph showing
the QE of the CCDs available in QSI 500 Series cameras at the time of printing.
Note that the non-anti-blooming, full
frame KAF-3200 and KAF-1603 have
the highest QE, peaking toward the
red end of the spectrum around
650nm. The anti-blooming, interline
transfer KAI-2020 and KAI-04022
have the lowest QE, peaking toward
the blue end of the visible spectrum
around 450nm.
Single-shot color CCDs
CCDs are inherently monochrome devices with varying response to different frequencies of
light. That varying response can be seen in the quantum efficiency graph above. Color
images are normally produced with CCD cameras by taking three (or more) images through
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red, green and blue filters. The resulting images are then combined using computer image
processing programs into a final color image.
Single-shot color CCDs, like those found in almost all general use digital cameras, are
made by placing red, green and blue filters over adjacent pixels in the CCD. The image
processing program then has to separate the three different color images and recombine
them into a single color image.
Single-shot color CCDs use a “Bayer
filter” with alternating red, green and blue
pixels covering adjacent pixels in a
checker board pattern as shown in the
image to the right.
50% of the pixels are covered in a green
filter, 25% are covered in a blue filter and
25% are covered in a red filter. This
arrangement is used because the
human eye is most sensitive to green
light. The green pixels correspond to
luminance and record the greatest detail
while the red and blue filters record
chrominance.
Courtesy Wikipedia
After the raw image is read from the
CCD, a demosaicing algorithm must be applied to the image to produce a complete set of
red, green and blue images by interpolating the missing pixel values. This is exactly what
normal digital cameras do, but it’s all hidden inside the camera’s electronics. You only see
the final processed image. With a CCD camera, the raw image is read into the camera
control program and then processed on your computer. This has the advantage that you
can directly manipulate the raw image to, for instance, vary the color balance.
Single-shot color models offer the easiest way to take color images of the night sky. The
trade off is reduced QE and detail because of the demosaicing and pixel interpolation.
Signal versus noise
For an astronomer, “signal” is the photons coming from the stars in the night sky. In an
ideal world, there would be steady stream of photons from every bright object and every
photon striking a pixel would be converted into exactly one electron in the CCD. Then the
number of electrons would be precisely counted and converted to a number telling the
photographer exactly how much light struck each pixel. Unfortunately, the process of
converting light to pixel values in a CCD image is governed by some fundamental physical
laws and other factors that introduce “noise” into an image. Noise is unwanted variations in
pixel values that make the image a less than exact representation of the original scene.
Noise in CCD images can manifest itself in multiple ways, including “graininess” in darker
background areas, “hot” pixels, faint horizontal or vertical lines that become visible in low
signal areas of the image, blotchy gradients between darker and lighter regions in a nebula,
a gradient from dark to light from one corner or side of an image to the other, and especially
as low contrast images — the result of a reduced signal to noise ratio. Achieving high
dynamic range, low noise images from a cooled CCD camera requires a basic
understanding of how CCDs work and the different sources of noise that can reduce the
quality of your images.
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Reducing noise in CCD images
CCD imagers have developed a standard set of calibration techniques to reduce or
eliminate different types of noise from CCD images. Calibrating CCD images requires
taking some special kinds of exposures that are then applied to the “light frames” taken of
the night sky. The calibration frames are called Dark Frames, Flat Fields and Bias Frames.
MaxIm LE and other CCD camera control software help gather these extra frames. After
the frames are gathered, MaxIm allows you to calibrate your images either automatically or
manually.
All the calibration frames should be collected during each imaging session with the CCD at
the same temperature used for the light frames. This will ensure the best possible
calibration of the final images. Many CCD imagers plan their night of observing to begin
taking the calibration frames as dawn approaches. That way, you don’t waste precious
dark time.
The image above is a single raw 6-minute image of the diffuse nebula M78 in Orion. Some bright stars are clearly
visible along with some nebulosity but there are also scattered bright spots around the image caused by “hot” pixels.
Dark Frames
Dark frames are used to subtract the build up of dark current from a CCD image. Dark
current is caused by heat. Similar to how CCDs convert the energy from a photon into a
stored electron, CCDs also convert the energy from heat into stored electrons. CCDs build
up “dark current” whether the CCD is being exposed to light or not. The rate that dark
current builds up is dependent on the temperature of the CCD and can be dramatically
reduced by cooling the CCD. Dark current builds up more slowly as the temperature of the
CCD is reduced.
Most pixels on a CCD build up dark current at a constant rate but that rate will vary slightly
from pixel to pixel. A subset of the pixels in a CCD will build up dark current at a
dramatically different rate from the average. These pixels are called “hot pixels” or “dark
pixels”. Hot pixels and dark pixels are both the result of slight imperfections introduced into
the silicon substrate of the CCD during the manufacturing process. Hot pixels are very easy
to see in a raw CCD image as a series of bright dots placed randomly around the image.
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6-minute Dark Frame
Above is a 6-minute dark frame taken during the same imaging session with the above
image of M78. Notice the brighter pixels scattered randomly around the image.
Note: The pixel values in this image have been stretched significantly to show the
variations in the dark frame. In reality this image is almost completely black with
perhaps a few hundred “hot” pixels. This is completely normal and a natural
consequence of how CCDs are manufactured.
MaxIm LE automatically scales the visible range of pixels to match the underlying data. In
the dark frame shown above the average pixel value is just 203 out of a possible 16-bit
dynamic range of 0-65,535. Seeing an automatically scaled dark frame or bias frame can
be a bit disconcerting for a new imager. Fear not, this “noise” will be almost completely
eliminated by subtracting a dark frame from your images.
Dark frames are subtracted from a light frame to remove the dark current from the image.
This subtraction removes the slight differences in dark current build-up from pixel to pixel
along with the larger variations caused by hot or dark pixels.
In general you’ll want to take at least 5 dark frames at each exposure used for your light
frames. If all your light frames were taken with 5-minute exposures, you’ll need to collect a
set of 5-minute dark frames. If you took both 5-minute and 10-minute light frames, you’ll
need a set of 5-minute dark frames and a set of 10 minute dark frames. There is a way to
reduce the number of dark frames you collect by using a set of bias frames but, in general,
you’ll achieve the best results taking dark frames with the same exposure as your light
frames.
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Original image
Original image minus dark frame
Look at the two images above. The top image is the original image as it came out of the
camera. The bottom image has had the average of 5 dark frames subtracted from it. Note
that the bright pixels have been virtually eliminated leaving a smooth black sky background.
Flat Fields
Flat fields are used to correct for any irregularities in your optical system, such as vignetting
or dust motes, and to adjust for any pixel non-uniformity inherent in the CCD. Pixels in a
CCD all respond slightly differently to light, typically within 1% to 2% across a CCD.
All optical systems have a “signature” which gets recorded on the CCD. This unique
signature is caused by how light travels through the telescope illuminating the CCD and
how each pixel responds to that illumination.
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The image above has been manipulated to highlight the effect of dust motes on a filter or CCD cover glass. Note the
3 darker circles. Because dust will tend to stay in one place over a night of imaging, the variation in pixel values caused
by the dust can be easily eliminated by properly applying a Flat Field.
A flat field is created by taking an image of an evenly illuminated subject. There are four
common ways to create flat fields.
Lightbox flats – Using a lightbox is usually the easiest way to create good flat fields.
There are a few commercial lightbox solutions, but many
astronomers make their own. You can find plans in The New CCD
Astronomy and The Handbook of Astronomical Image Processing
as well as online. Search for “Telescope light box”.
Twilight flats – There is a brief time after the sun sets or just before it rises when
the sky is appropriate for creating flat frames. Too early and the sky
is too bright. Too late and stars will begin to show up in the image.
Dome flats –
If your telescope is in an observatory, you can take dome flats. A
dome flat is created by aiming your telescope at a white card
placed somewhere on the inside of the dome.
Sky flats –
Taking sky flats requires taking dozens or hundreds of images with
the telescope pointed at the sky with tracking turned off. All the
images are combined into a master flat to remove the effect of any
stars moving through the field. Sky flats require more time than the
other three options so few amateurs take sky flats. We recommend
reading the section on Sky Flats in the Handbook of Astronomical
Image Processing for additional details on this technique.
Good flat fields require an exposure time such that the pixel wells are filled to approximately
half their full capacity. With a QSI 500 Series camera you should strive to achieve average
pixel values between 20,000 and 30,000 out of a total of roughly 65,000. You should
experiment with exposure times to yield that result. Pixel values are commonly called
“ADUs”, short for Analog to Digital Units.
You’ll need to take enough flat fields to average out the noise and then take a series of dark
frames (called flat-darks) using the same exposure you used for your flat fields. Just as with
light frames, the flat-darks are subtracted from the flat fields to remove any contribution from
dark current. Taking 16 flat fields and 16 flat-darks will yield excellent results. Luckily
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because flat fields tend to use fairly short exposures, you can often take a full series of flat
fields and flat-darks in just a few minutes.
The resulting master Flat Field is used to scale the pixel values in the light frame,
eliminating the effects of pixel non-uniformity, optical vignetting and dust on the optical
surfaces.
Bias Frames
A Bias Frame is a zero-length (dark) exposure intended to measure just the difference
between the pixels plus any additional noise added during the process of reading the image
from the CCD and converting it into a digital image file. Because the CCD pixels are
emptied immediately before the image is read from the CCD, only a small amount of dark
current has had a chance to build up, but that rate of accumulation varies slightly for every
pixel. Also, reading an image from a CCD is not instantaneous. Pixels near the bottom of
the CCD are read later than pixels closer to the top of the CCD so pixels toward the bottom
tend to have slightly higher pixel values than pixels closer to the top.
One common use of bias frames is for scaling dark frames. By subtracting a bias frame
from a dark frame, you end up with a “thermal frame.” A thermal frame contains pixel
values showing just the effect of dark current. Because dark current in any given pixel
accumulates at a constant rate, a thermal frame allows you to predict with reasonable
accuracy how much dark current there would be for different length exposures. However,
given the opportunity, you’re generally better off taking dark frames that match the exposure
times of your light frames.
Here is an example bias frame. Note again that this image has been automatically stretched to show
variations in the pixel values. MaxIm LE does this automatically when you view an image file. All
the pixel values in the original image fall between 181 and 221 out of a possible range of 0-65,535,
meaning that the unstretched image would appear almost perfectly and uniformly black.
Bias frames can also be used to analyze the read noise in a CCD camera. You can learn
more about that process on the QSI web site at http://www.qsimaging.com/ccd_noise.html.
Taking bias frames is easy and takes only a couple of minutes. When you’re taking your
dark frames and flat fields, also take a series of at least 16 bias frames. That completes
your full set of calibration frames.
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Stacking Images
After calibrating each of your raw images with dark frames, flat fields and bias frames,
combining or “stacking” multiple sub-exposures can be used to further reduce the noise in
your images. Stacking multiple images with a pixel-by-pixel average or median combine
tends to increase the signal to noise ratio (SNR) of the combined image. This is because
random variations in pixel values tend to cancel each other out when multiple images are
combined, resulting in a smooth background, while non-random pixels, the bright objects in
the night sky you’re trying to take a picture of, reinforce each other getting you closer to a
true representation of the patch of sky you’re imaging.
The benefits of stacking images can be clearly seen by comparing an individual frame to a
pixel-by-pixel average of multiple frames.
Individual dark-subtracted image of M78
Average combine of 9 dark-subtracted images of M78
Averaging 9 separate images increases the signal to noise ratio of the final image, allowing
the faint nebulosity in M78 to become visible and smoothing the black sky background.
Adding more frames would further improve the results although you do end up in a situation
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of diminishing returns. Combining 18 frames will not yield a final image twice as good as
combining 9 frames.
Also note that in some cases, doing a “median combine” rather than an “average combine”
may yield better results. A median combine is recommended if several of the individual
frames have unique anomalies such as bright pixels caused by cosmic rays, satellites,
airplanes, etc. With at least 5 images, a median combine completely eliminates extreme
pixel values that occur in individual frames.
Color images
Unless you’re using a single-shot color camera such as the QSI 583c, producing color
images requires taking separate exposures through different colored filters and then
electronically combining the separate color channels. The most common method used by
amateur astronomers for color imaging is called LRGB, where separate color images are
taken through red, green and blue filters and combined with a set of “luminance” images
taken through a luminance filter. The luminance filter is required because CCDs are
generally responsive to frequencies of light that can’t be seen by the human eye. The
luminance filter blocks the infrared (IR) and ultraviolet (UV) frequencies that fall outside the
range of human vision.
The luminance filter transmits most of the visible light coming from the object. Because the
individual frames taken through the red, green and blue filters block roughly ⅔ of the total
visible light, the luminance image will often reveal subtle details not apparent in the
individual color frames. This actually works out quite well since the human eye is much
more sensitive to changes in brightness than it is to changes in color. Combining a colorbalanced RGB image with a luminance image will yield an LRBG image that the human eye
would perceive as being very close to the true colors of the object with more fine detail than
is present in the RGB image on its own.
MaxIm LE can be used with your QSI 500 Series camera to collect and catalog the various
filtered images that you’ll need to create LRGB images. As with any images, you’ll want to
collect multiple frames through each filter and then calibrate and combine them in order to
reduce the major sources of noise. After calibration, you’ll have a master luminance image
plus master red, green and blue images. Those master color frames are combined into
your final image. In addition to the color image tools in MaxIm you can do further
processing of your images in Adobe Photoshop or similar photo manipulation programs to
yield impressive final results.
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4
Section
G U I D E
Taking Images with your
QSI 500 Series Camera
Launch MaxIm LE
Note: This section uses MaxIm LE as the camera control application. If you use a different
camera control application, it will support similar operations.
Launch MaxIm LE by double-clicking the MaxIm LE icon on your desktop or select
“Programs > MaxIm LE > MaxIm LE” from the Windows Start menu. The MaxIm LE
window should open looking similar to this:
Your window may look slightly different. If the Screen Stretch and Information windows aren’t open, open them by
selecting “Screen Stretch Window” from the View menu, then selecting “Information window” from the View menu.
You can move those windows around your screen to position them where they are most convenient.
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Camera Control Window
Select “Camera Control Window” from the View menu to open the Camera Control
Window.
MaxIm should open the window and display the Setup tab. If another tab is displayed, click
the Setup tab. MaxIm may recognize your QSI camera and automatically show it as the
default camera in the Main CCD Camera field. If so, the Camera Control Window will look
like this:
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If you don’t see “QSI Universal” listed in the Main CCD Camera field, click the “Setup”
button in the upper left corner under Main CCD Camera. The window below will open.
Select “QSI Universal” from the pop-up menu. Click OK.
That will take you back to the Camera Control Window. Click the “Connect” button to
establish communication between MaxIm and your QSI camera. If MaxIm connects
properly the Camera Control window will look like this:
Note that the current temperature of the CCD is displayed in the “Main CCD Camera” field
toward the upper left of the Camera Control window. The “Setpoint” is the temperature that
camera will cool the CCD to, and may be different than shown above.
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Cool the CCD
To set the CCD cooling temperature you must first turn Cooling on by clicking the “Cooler
On” button just to the left of the Connect button. After turning cooling on, the Camera
Control window will look like this:
The camera will immediately begin cooling the CCD to achieve the current setpoint
temperature. To select a different setpoint temperature, click the “Cooler” button at the
bottom left of the Main CCD Camera field. That will open the “Set Camera Cooler” window
on top of the Camera Control window.
Enter a new temperature in the Setpoint field and click OK.
The camera will automatically select the right amount of power to apply to the coolers to
drive the CCD to the correct temperature. The Main CCD Camera field will show the CCD
temperature setpoint, the current CCD temperature and the amount of power being applied
to the CCD. The camera should reach the setpoint temperature and stabilize within 5 to 10
minutes depending on conditions and the amount of cooling required.
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Note:
Please refer to the Cooling the Camera discussion in Section 2 Camera
Features and Controls for in-depth information on cooling your 500 Series
camera and the available cooling options.
Focusing with MaxIm LE
Achieving precise focus is critical for producing high quality astronomical photos. This
seemingly simple task is surprisingly difficult when using the long focal lengths typical of
astronomical telescopes. Fast telescopes with small focal ratios are great for
astrophotography, but they make focusing even more of a challenge. The smaller the focal
ratio, the shorter the critical focus zone. With some optical systems, the size of the critical
focus zone can be less than 100 microns (0.1 millimeters), or roughly 0.003 inches.
MaxIm LE includes a Focus tab to assist with achieving critical focus. In the Camera
Control Window, click the Focus Tab.
The Focus tab allows you to take a continuous series of short exposures while adjusting the
focus of your telescope or other lens. As stars come into focus they produce a smaller disk
of light with more of the total light from the star being focused into a smaller area. The
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Focus tab window should be set as shown above. You may need to adjust the exposure
time in the “Seconds” field to the time necessary to see a few bright stars. Setting the
exposure time as short as necessary to see a few bright stars allows you take more focus
images in a shorter period of time, generally allowing you to achieve reasonably sharp focus
fairly quickly. When you are satisfied with the focus, click “Stop”.
Note:
The Inspect tab next to the Focus tab can help you achieve critical focus
by analyzing the area around the brightest point light source in an image. Review
the MaxIm LE online help on focusing for additional details.
Take a single image
After connecting to the camera, letting the camera stabilize at the desired temperature, and
achieving critical focus, you’re finally ready to begin taking “light frames”.
Click on the Camera Control window to make it active. If the Camera Control window is not
visible, select “Camera Control Window” from the View menu. Click the “Expose” tab. The
window will look similar to this:
Click “Light” under the “Type” to select a “light frame.” If you have a camera with a color
filter wheel, select the filter that you wish to use for this exposure. On a QSI 500 Series
model with internal color filter wheel, Filter 4 by default contains the “L” or luminance filter.
Set the exposure length in the Minutes and Seconds field.
Tip: The Seconds field can accept values up to 32767 seconds so you won’t need
to use the Minutes field unless that’s more natural for you.
When the settings in the Expose tab are set properly, click the Expose button to begin the
exposure. While the camera is exposing the image, the Status LED on the back of the
camera will flash red. When the exposure is complete the Status LED will flash yellow while
the image is being downloaded.
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View the image in MaxIm LE
When an exposure has completed, MaxIm will automatically download and display the
image in a new window.
After downloading the image, examine it to see if the target is properly framed and the
exposure time is appropriate. The best astronomical images are achieved when the full
dynamic range of the CCD is utilized.
If you like the image, save it by selecting “Save” from the File menu. If you need to adjust
the framing, focus or exposure, make the necessary changes then click the “Expose” button
again. When you’re happy with the image, save it with an appropriate name so you
remember what the target, temperature and exposure settings were. After a long night of
imaging, it is difficult to remember what settings were used with which image files.
Tip: The FITS file format used as the default file format by MaxIm LE and most
astronomical image processing programs stores a number of settings about the
image inside the file. MaxIm LE automatically stores the exposure time, filter
settings, and CCD temperature among other values associated with each image.
MaxIm will also store your name, telescope specifications and location into the
FITS headers if you first enter it in the FITS Header tab of the File > Settings…
window. To see the information stored in the FITS header of an image file, select
“FITS Header Window” from the View menu.
Take a series of images
Achieving the best astronomical images generally requires gathering a lot of light. Taking
multiple sub-exposures of, say, 5 minutes, is generally easier than trying to take a single 60
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minute image. Tracking errors, improper polar alignment, airplanes, satellites, and cosmic
rays all conspire to make it difficult to be successful with very long exposures. Plus it’s a lot
less frustrating to throw away one 5-minute exposure out of a total of 12 than a single 60minute exposure.
MaxIm makes taking multiple sub-exposures easy. It’s even possible to set up an entire
night of images and then go to sleep. To set up a sequence of images, bring the Camera
Control Window to the front and click on the “Sequence” tab.
Establish a base file name for the sequence of images by entering a text string in the
“Autosave Filename” field. All the images taken in the sequence will begin with that base
filename. Set “Start at” to 1. This determines the starting sequence number applied to
each series of images.
Click the black arrowhead to the right of “Options” along the right edge of the Sequence tab
window. The Options menu will popup. Select “Setup Sequence…” from the Options
menu. This will open the “Setup Sequence” window.
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The Setup Sequence window allows you to set up 16 different groups of images to take
during a single automated sequence. In the window above, we show 6 different steps in the
sequence. MaxIm LE will take five 360 second light frames each with the red, green and
then blue filters, ten 360 second light frames with the luminance filter, 12 360 second dark
frames and 16 bias frames. The total duration of the sequence is shown along the bottom
under “Duration.” This sequence of images will take 13,502 seconds, or roughly 3 hours
and 45 minutes.
The default behavior of MaxIm LE is to take one image in each grouping (e.g., one “R”
image followed by 1 “G” image, etc.) cycling through all the active groups. If you prefer to
take all the “R” images followed by all the “G” images, etc., click the black arrowhead next to
Options along the bottom of the Setup Sequence window and select “Group by Slot”.
Note:
The “Suffix” field will be appended to each image filename along with a
sequence number. So the full filename of the first light frame taken through the
red filter would be “M78 QSI 0C-001-R360.fit”. This name identifies the target
(M78) the camera model (QSI), the CCD temperature (0C), the sequence number
(001) and the filter and exposure length (R360). You can of course choose your
own naming scheme.
When you’ve setup the sequence of images you wish to take, click OK to return to the
Camera Control window. Click the “Start” button to begin the sequence. All the images in
the sequence will be run automatically, including moving the filter wheel to the appropriate
filter, until the sequence is complete. You are free to perform other tasks, or even take a
nap, until the sequence completes. Review the MaxIm LE online help regarding
Sequences for additional details.
Image Calibration
Image calibration is the process of removing or reducing predictable types of noise and
variations in pixel brightness not caused by light from your subject striking the CCD. The
calibration frames should include:
1. 5 or more Dark frames
You’ll want at least 5 dark frames taken at each exposure length used for your
light frames. If all your light frames were taken with a 5-minute exposure you’ll
only need one set of dark frames. If you took 2-minute, 5-minute and 10minute exposures you’ll need a set of dark frames for each exposure length.
2. 16 Bias frames (for scaling dark frames if necessary)
Plus optionally…
3. 5 Flat field frames
Note: If you took images through different filters, for the best results you’ll want
separate flat fields with each filter to record the unique optical signature produced
through each filter.
4. 16 flat-darks
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The above numbers represent the minimum of each type of frame you should use. Taking
more of each type of frame will further reduce the noise present in each calibration master
image and improve your final results.
Why you take different types of image calibration frames was discussed in some depth in
the CCD Imaging Overview section. This section covers how to take the required
calibration frames.
Dark Frames
Dark frames are used to subtract the build-up of dark current from raw CCD images.
Subtracting dark current is generally considered the most important image calibration step.
In the previous section, we showed how to use the Sequence tab to automatically take a
sequence of images. Adding the required dark frames to an automated sequence is often
convenient because taking dark frames consumes a lot of time. You need at least as many
dark frames as you take for each type of light frame, twice as many darks is even better.
Taking the dark frames in the same sequence as the light frames also ensures that the
environmental conditions are as close as possible to the conditions when you took the light
frames. This ensures the closest match when subtracting dark frames from light frames.
An exception to this rule is if all the dark time during the night is reserved for taking light
frames. Dark frames can be taken after the sun starts to light up the sky as long as no stray
light reaches the CCD and the camera can maintain the same CCD temperature as the
morning air starts to heat up.
To take a series of dark frames, either add them as an additional group in the Setup
Sequence window or setup a new sequence of just dark frames at a convenient time during
the imaging session. If you’re taking 5 exposures each with the R, G and B filters, take at
least 10 dark frames using the same exposure. Taking more dark frames reduces the
noise in the combined dark master, producing higher quality images.
Bias Frames
Bias Frames record just the subtle variations in the zero level of each pixel plus any noise
introduced when reading the image from the CCD. Taking a complete set of bias frames
takes only a couple of minutes so in general you should plan on always taking at least one
set of bias frames during each imaging session.
To take a series of bias frames, either add them as an additional group in the Setup
Sequence window, or setup a new sequence of just bias frames at a convenient time during
the imaging session. Take at least 16 bias frames at the same temperature as your light
and dark frames.
Flat Fields
Flat fields record any irregularities in your optical system, such as vignetting or dust motes,
and the slightly different light sensitivity of each pixel on the CCD. Some astroimagers
consider flat fields to be optional. While calibrating images with flat fields does not have as
dramatic an effect on CCD images as applying dark frames, flat fields are nevertheless
important for producing the best images with even illumination and the highest possible
signal to noise ratio.
Most astronomers take their flat fields either in the evening before the sky gets completely
dark or in the morning as dawn approaches. If you’re taking twilight flats the timing of those
images is critical as you have only a few minutes when the sky is appropriate for taking
twilight flats. As with dark frames and bias frames it is important that flat field frames are
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taken with the CCD at the same temperature as your light frames. If you’re taking LRGB or
other filtered images, ideally you should take a set of flat fields through each filter.
Setup your telescope and possibly your light box to take your preferred style of flats. Adjust
the exposure so the average pixel is filled to approximately half its full well depth. With QSI
500 Series cameras you should strive for pixel values of roughly 30,000 ADUs. As with
dark frames, you should take at least as many flat frames as the light frames you took
through each filter. Taking additional flat fields will produce a master flat with less noise,
yielding higher quality images. Do not change your focus. To get correct flat fields, it is
important that the focus be identical to the focus used for the light frames.
Flat Darks
As with any exposure using a CCD camera, dark current builds up while taking a flat field
image therefore the dark current must be subtracted with a dark frame taken at the same
exposure as the flat field. Taking flat-darks is easier and less time consuming than regular
dark frames because the exposure time of flat field images is typically much shorter than
your light frames. If you take flat field images, it is critical that you also take a series of flatdarks. They’re easy to take with the shorter exposure, so take at least 15 flat-darks.
Manual Image Calibration
MaxIm LE supports both automatic and manual image calibration. This section describes
basic manual image calibration in MaxIm LE. For complete instructions on calibrating
images, please see the online help in MaxIm LE.
Subtract Dark Frames
Begin by creating a master Dark Frame for each exposure length. A master dark frame is
created by combining all the individual dark frames using an average or median combine.
See the section below Combine Frames in MaxIm LE for detailed instructions on
combining multiple images.
Tip: In general, an average combine of multiple images will yield a combined
image with slightly less noise than a median combine, but this requires that none
of the frames being combined have any anomalous groups of light or dark pixels
caused by, for instance, cosmic rays.
Other programs, such as MaxIm DL, include additional combine methods that
attempt to provide the low noise of an average combine with the anomalous pixel
rejection of a median combine. You will need to experiment to achieve the best
results.
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Dark frame showing two cosmic ray hits in lower right hand quadrant
Inspect your dark frames for cosmic ray strikes or other anomalous pixel groupings. The
dark frame above shows two cosmic ray hits in the lower right quadrant of the image.
Cosmic rays are energetic particles originating from somewhere in space. They can come
from any direction and depending on the angle that they strike the CCD can be very long if
they are nearly parallel with the CCD or just a bright circle if they strike perpendicular to the
CCD.
If multiple dark frames in your set each have cosmic ray hits, doing a median combine of all
the images may yield a better combined image than averaging just the clean frames.
Experiment to get the best results.
After you’ve created your master dark frame for a given exposure length, subtract it from
each of the light frames with that same exposure. Do this by selecting “Pixel Math…” from
the Process menu.
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Screenshot showing Pixel Math command ready to subtract a master dark frame.
Select your light frame for Image A at the top and your master dark for Image B. Select
“Subtract” for the operation. Click OK. You should see many of the bright pixels scattered
around the light frame, disappear or get visibly darker. Do this with each of your light
frames. After dark subtracting the individual light frames, the light frames can be combined
into a master light frame. If you took multiple images through different filters you will need to
create a master light frame for each color.
Scale by Flat Fields
Scaling dark subtracted images by flat fields follows a similar process to subtracting dark
frames.
Note:
Taking proper flat fields can be tricky. If the flat fields aren’t exposed and
processed properly, scaling an image by an improper flat field can produce results
worse than not calibrating with flat fields at all. Experiment and practice for the
best results.
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1. Produce a master dark flat following the steps above for creating a master dark frame.
2. Subtract the master dark flat from each of the flat fields.
3. Produce a master flat field by averaging the dark-subtracted flat field images.
4. Finally, divide the master flat field image into each of the dark-subtracted light frames.
Save the resulting images with names that identify the frames as dark subtracted and
scaled by a flat field.
See the section below Combine Frames in MaxIm LE for how to combine the now
calibrated individual frames into a master light frame. If you took multiple images through
different filters, you’ll need to create a master light frame for each filter (e.g., red, green,
blue, luminance for LRGB images).
Automatic Calibration in MaxIm LE
The section above described manual image calibration in MaxIm LE. This section
describes using automatic image calibration in MaxIm. Many astrophotographers prefer to
do all their image calibration manually in order to maintain the greatest control over the
calibration process, but used properly, automatic image calibration can save significant
amounts of time and yield excellent results. For complete instructions on calibrating
images, please see the online help provided with MaxIm LE.
Begin by gathering all of your calibration frames into the same directory as your light
frames. This makes it easier for MaxIm to automatically find and characterize each of the
calibration frames.
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Launch MaxIm LE. Choose “Set Calibration” from the Process menu. That will open the
Set Calibration window.
By default, MaxIm expects to calibrate images with bias frames, dark frames and flat fields.
For this example we’re only going to show calibrating with bias frames and dark frames.
Note: MaxIm also has a Calibration Wizard that steps you through the process of
setting up your image calibration. For details on the Calibration Wizard please
consult the online help in MaxIm LE.
If you’re not calibrating with flats, as in this example, uncheck the three “Flat” checkboxes
along the top of the Set Calibration window.
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In the “Auto-Generation” panel near the bottom of the window, click the “…” button to the
right of the text field and navigate to the folder that contains your images. In this example
the images are contained in:
My Documents\QSI\Astro Images\M78 QSI 504 060924\
Click the checkbox next to “Include Subfolders” if you’ve organized the images and
calibration frames into subfolders within the main folder.
Click the “Auto Generate” button in the lower left-hand corner of the Set Calibration window.
MaxIm will search the specified folder for any calibration frames and automatically organize
them into different calibration groups based on the type of frame, length of exposure, CCD
temperature, etc. This is possible because the FITS file format records all the information
about each image in the FITS Header attached to each FITS file.
After auto-generating your calibration groups, the Set Calibration window will look
something like this:
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The upper panel lists the groups of calibration frames that MaxIm identified. The first
calibration group should be selected. The lower “Group Properties” panel lists the files in
the selected calibration group. Click on the group labeled “Dark1” in the upper panel to see
the files in that group.
For each calibration group, you can select whether the master image for the group should
be created by averaging each pixel in the individual frames or using the median value of
each pixel. Setting the “Combine Type” to average will generally yield the lowest noise
master frame but any irregularities in any of the images, such as from a cosmic ray hit, will
show up in the master image. Setting the combine type to Median eliminates any
excessively dark or light pixels in an individual image from affecting the master but produces
a master image with slightly more noise than an average combine of clean individual
calibration frames.
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If MaxIm correctly identified all the calibration groups you created, you can click OK to close
the Set Calibration window. Optionally you can click the “Replace w/Masters” button next to
the Auto-Generate button. When Replace w/Masters is pressed, MaxIm will combine all the
images in each calibration group and save the combined master image in the same
directory as the individual frames. It will then modify the calibration groups to use each
master frame. Using “Replace w/Masters” saves a little time while calibrating images
because MaxIm only has to load and process one master file as opposed to all the
individual frames.
After clicking “Replace w/Masters” the Set Calibration window will look like this:
Note: MaxIm assigns a name to the master calibration frames that shows all the
unique characteristics about the calibration group used to create it.
Click “OK” to close the Set Calibration window.
Calibrate Images in MaxIm LE
Now that you’ve told MaxIm about all your calibration frames you’re ready to calibrate your
light frames. We’re going to show an example of calibrating the “luminance” or “L” images.
If you’re taking LRGB images, the same techniques will be applied to processing the
images taken through the red, green and blue filters.
Open all the luminance images in MaxIm LE. In this example 9 luminance images were
taken with an exposure of 360 seconds each. All the luminance images were given a
filename suffix of “L” when the image sequence was setup using the Sequence tab in the
Camera Control window. Select multiple files from within a folder and drag them all at once
into MaxIm or select “Open…” from the File menu and open individual or multiple files in a
single operation.
With the files open in MaxIm, select “Calibrate All” from the Process menu.
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MaxIm will apply each of the calibration groups you specified in the Set Calibration step to
each of the open images.
You can then choose to save the calibrated images or just leave them open in MaxIm.
Tip:
Be careful when saving the individual calibrated images not to overwrite the
original image files. It is often useful to go back to the original uncalibrated
images.
Combine Frames in MaxIm LE
After you’ve calibrated the individual light frames, you can then combine them into a master
frame. Continuing with the example above, we’ll combine the 9 luminance images into a
master luminance image.
Select “Combine…” from the Process menu. If you’re working with very large files, you can
also choose “Combine Files…” from the File menu. It performs exactly the same function
but works on files from disk rather than memory. The “Combine” command works best if all
the images you want to combine fit in your computer’s memory.
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The dialog box above will open showing a list of all currently open files on the left. Select
individual image files and then click the “>>” button to add them to the list of Selected
Images or click the “Add All” button to add all the images. Click OK.
This brings up the Combine Images dialog, which performs two related functions. It aligns
and then combines the individual images. Alignment is important because unless you have
absolutely perfect polar alignment and tracking, the position of individual stars will shift
slightly between images.
MaxIm LE provides 3 types of manual alignment. Other programs, such as MaxIm DL
provide additional types of alignment including fully automatic alignment. For this example
we’re going to use the Align Mode, “Manual 2 stars.” This 2 star alignment will shift and
rotate individual frames to line up the stars in the images.
MaxIm makes manually aligning the images painless. If you’re aligning on stars, click the
checkboxes next to “Use Centroid” and “Auto Next”. With “Use Centroid” MaxIm will
calculate the center of mass of a point object like a star allowing sub-pixel alignment. With
Auto Next set, each time you click on an image to pick the alignment star, MaxIm will
automatically proceed to the next image. Select a star fairly near the edge of the first image
and click on it. That sets the position of the first star in the alignment process. If “Auto Next”
is set, MaxIm will display the next image file. Click on the same star in each image.
In the dialog box below we are already half way through the alignment process. Note that
the “Center Point” is set to “23, 57” and the “Star 2” button is depressed.
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The first image file is again the top
window in MaxIm. Select a second
alignment star near the opposite edge
of the image. Repeat the process by
clicking on the second star in each
image. When you click on the star in
the last image, MaxIm will make a bell
sound indicating that the alignment
process is complete.
Make sure the Output field is set like
you want: Sum, Average or Median.
Average will generally yield the best
results if none of the images have any
cosmic ray hits or other anomalous
errors. Click OK to combine the
images. MaxIm will open a new
window with the combined image.
Combined image of M78
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If everything was done correctly the calibrated and combined image should show additional
detail with less noise and greater contrast than the individual frames. Changing the range
of displayed brightness levels in Screen Stretch window will show additional detail in
different parts of the raw image file. Save the image with a name that allows you to identify
this image as a combined master image.
MaxIm provides additional tools for manipulating images. Please refer to the online help on
Image Processing in MaxIm for additional details. After performing image calibration in
MaxIm, many astronomers prefer to move the individual or combined image files into Adobe
Photoshop or other dedicated image processing program for further processing.
Binning
Binning allows you to combine multiple pixels into what are effectively larger pixels with up
to sixteen times the surface area and sensitivity as an individual pixel. The standard binning
mode is 1x1 meaning that each logical pixel is equal to one physical pixel. The QSI 500
Series supports symmetrical and asymmetrical binning up to at least 3 pixels in either axis.
Some models offer additional binning options. Larger binning modes like these provide
increased sensitivity and dynamic range at the expense of resolution. Asymmetrical binning
(e.g. 1x3 or 3x2) is not commonly used but can be very useful for specialized applications
such as spectroscopy.
The following image illustrates how rows and columns of pixels are combined when binning an
image. Notice how the effective dimensions of the CCD changes with the degree of binning.
1x1 Binning
3326x2504
2x2 Binning
1663x1252
3x3 Binning
1108x834
QSI 583 image size
Binning other than 1x1 is typically used in two different situations. First, the human eye is
much more sensitive to subtle changes in image brightness than it is to small changes in
color. This can be taken advantage when producing color images by taking luminance
images through the “L” filter binned 1x1 and red, green and blue images binned 2x2. When
combined with the luminance image the 2x2 binned color image is almost indistinguishable
from using 1x1 binning for the color frames.
The second situation where 2x2 or higher binning is used is when seeing conditions don’t
support high resolution imaging. If each pixel on your CCD “sees” 2 arc seconds of the sky
through your telescope and the local seeing conditions are only 4 arc seconds, you won’t
benefit from the increased resolution offered by 1x1 binning. In this case, binning 2x2 will
yield optimal results in a shorter amount of time.
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Select the binning mode for a single exposure in MaxIm LE on the Settings tab of the
Camera Control window.
Note:
MaxIm automatically adjusts the Width and Height fields to represent the
size of the resulting image. In the example above 2x2 binning has been selected.
This reduces the size of the resulting image of the QSI 504 from 768x512 to
384x256.
You can also select different binning modes when setting up a sequence of images under
the Sequence tab of the Camera Control window.
In the example above, the red, green and blue filtered images will be taken with 2x2
binning. The luminance image through “Filter 4” will be taken with 1x1 binning. Note that in
this sequence the color images are set for an exposure of 240 seconds. This would require
a separate set of 240 second dark frames for the color exposures in addition to the 360
second dark frames for the 1x1 luminance frames.
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Note:
When using binning other than 1x1, the pixels are combined inside the
CCD before reading and converting the combined pixel charge to a numeric
value. This results in lower overall noise than reading each pixel separately and
combining them mathematically in your computer. With 2x2 binning for
instance, only one pixel value (representing a square of 4 physical pixels) is fed
through the CCD output amplifier resulting in ¼ the noise compared to reading
each of the 1x1 pixels separately.
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Using the internal Color Filter Wheel
Some QSI 500 Series cameras include an internal 5-position color filter wheel. The color
filter wheel is controlled automatically by MaxIm LE or other camera control software. If you
ordered LRGB filters with your camera, the
default order of the filters is as shown below:
1. Red
2. Green
3. Blue
4. Luminance
5. Empty
In the picture above with the front cover
removed from the camera, filter position 5 is shown empty over the shutter opening. Note
that the dichroic filters supplied with 500 Series cameras reflect the light not passed by the
filter (e.g. the red filter reflects cyan). Specify which filter to use for a single exposure in the
Expose tab of the Camera Control window by selecting the filter in the pop-up menu
In a sequence of images, you can specify a different filter for each sequence group. Refer to
the Setup Sequence window in the previous section. That sequence shows four sequence
groups, one each through the Red, Green, Blue and Luminance filters (shown as Filter 4).
Before each image is exposed the correct filter will be rotated into position.
For information on removing the front cover of the camera to add, remove or clean the color
filters, refer to the Care & Maintenance section.
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Shutting down your camera
QSI cameras can safely be turned off by removing the power cable at any time, however it
is best to let the temperature of the CCD rise close to the air temperature before removing
power.
Click on the Setup Tab in the Camera Control window. Click the Cooler Off button to turn
off the CCD cooler. The fans will continue to run dissipating heat from the thermoelectric
coolers. When the temperature of the CCD begins to stabilize near the air temperature,
click Disconnect to disconnect from the camera.
Unplug the power plug from the camera.
Controlling your camera with other software
QSI camera drivers are included on the installation CD for MaxIm DL from Diffraction
Limited and CCDSoft from Software Bisque. Follow the instructions in the installer if you
want to control your QSI 500 Series camera with either of these applications.
You can also write custom applications to control your QSI camera on Microsoft Windows
or Linux systems using our ASCOM-compatible Windows COM API or Linux API.
For complete details on the Microsoft Windows or Linux API and other applications that
please visit the Software and Drivers page on the QSI web site,
http://www.qsimaging.com/software.html.
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5
Section
G U I D E
Guiding
The QSI 500 Series camera can be used as you main imaging camera or as an autoguider.
MaxIm LE supports the following cameras as autoguiders. Other camera control software,
such as MaxIm DL support additional autoguiders with a QSI camera.
Autoguider support in MaxIm LE

Fishcamp Starfish

Any QSI camera

Meade DSI Pro, DSI Pro II, DSI Pro III

Any recent SBIG camera

Orion StarShoot

Video DirectShow

Orion StarShoot Autoguider

Lumenera

Starlight Express Lodestar
QSI 500 Series cameras have a Guider port on the bottom of the camera. This port sends
guider correcting signals to your telescope mount. Connect the included guider cable from
the camera Guider port to the AutoGuider port on your telescope mount. The guider
correction signals output by the QSI 500 will work with most modern telescope mounts
using the included guider cable.
The photo to the left shows the
guider cable connected to the
AutoGuider port on a Losmandy
Gemini System. Please refer to
your camera and mount
specifications to confirm your
mount is compatible with the
signals from the QSI 500 Series
camera. QSI offers an optional
Guider Break-Out Box (GBOB) for
connecting to older or nonstandard mounts. Please see the
QSI web site for complete details.
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Using an AutoGuider
This section provides basic instructions on how to use your QSI 500 Series camera as your
main imaging camera and set up a separate camera on a guide scope for guiding. For this
example, we’re using a Meade DSI Pro as the autoguider. For complete instructions on
guiding, including a step-by-step tutorial, please see the Online help in MaxIm LE.
Setup your QSI 500 Series camera as described above. Hook up your guider camera to
your guide scope and connect the guider camera to your computer.
Go to the Setup tab of the Camera Control window. Click the Setup button in the
Autoguider panel.
Follow the instructions that came with your autoguider camera to enable and configure the
camera. Click OK to return to the Setup tab of Camera Control Window. Click Connect. If
your cameras are hooked up and configured correctly, the status panels for each camera
will show the current status of your main CCD camera and your Autoguider.
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Click the “Guide” tab to the left of the Setup tab. The Start button will be enabled if the
autoguider camera was setup correctly.
Click the black arrowhead to the right of “Options” below the Stop button and select “Guider
Settings.”
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In the guider settings window, make sure that “Main Relays” is selected in the “Control Via”
pop-up list under Autoguider Output. This instructs MaxIm to send the autoguider control
signals through the Guider port on the QSI 500 Series camera. If your autoguider camera
also has a guider port, you can select “Guider Relays” to send the signals through the
autoguider camera. MaxIm supports additional methods of generating the correct control
signals. See the online help in MaxIm LE for complete details. Click OK to close the Guider
Settings window and return to the Guide tab of the Camera Control Window.
You may need to focus your guide scope. You can take an image with your guide camera
by pressing the Start button. Set the exposure only as long as necessary to still yield welldefined stars. Shorter exposures allow quicker cycles between guiding exposures and
smoother guiding.
The first time you press Start with a new exposure length, MaxIm LE will automatically take
a dark frame. Follow the instructions on screen. Press Start as necessary to take
additional images while focusing your guide scope. Stop when you are satisfied with the
focus and exposure length.
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MaxIm LE automatically selects the brightest star as the guide star.
You are now set up for guiding. Continue with instructions in the online help in MaxIm LE to
calibrate your autoguider and begin tracking the selected guide star.
For complete instructions on autoguiding in MaxIm LE please refer to the “Autoguiding”
section of the online help in MaxIm.
Using a QSI 500 Series Camera as an AutoGuider
Your QSI 500 Series can be used as an autoguider with another camera as your main
imaging camera. If using MaxIm LE, the main CCD camera must be set as a QSI camera
or “No Camera.” The full version of MaxIm DL and CCDSoft support additional options.
Note: This section provides basic instructions on how to use your QSI 500 Series
camera as an autoguider. For this example, there is no main CCD camera. For
complete instructions on guiding, including a step-by-step tutorial, please see the
online help in MaxIm LE.
Click the Setup tab of the Camera Control window. Click the Setup button below Main CCD
Camera and select “No Camera” under Camera Model and click OK to return to the
Camera Control Window. Click the Setup button below Autoguider and select “QSI
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Universal” under Camera Model and click OK to return to the Camera Control Window.
Click Connect.
Click the Guide tab and again click the black arrowhead to the right of “Options” below the
Stop button and select “Guider Settings.” Select “Guider Relays” in the “Control Via” pop-up
list under Autoguider Output. This instructs MaxIm to send the autoguider control signals
through the Guider port on the QSI 500 Series camera now being used as the autoguider.
Click OK to close the Guider Settings window and return to the Guide tab of the Camera
Control Window.
Everything else in the section above Using an Autoguider applies when using the QSI 500
Series camera as the autoguider. Continue with Using an Autoguider above for additional
details.
Note:
For complete instructions on guiding, including a step-by-step tutorial,
please see the Online help in MaxIm LE.
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6
Section
G U I D E
Accessories
T-mount adapter
The T-mount adapter plate attaches to the front of the camera body.
It comes standard on all QSI 500 Series cameras. The T-mount
adapter is threaded with standard T-mount threads, 42mm diameter
by 0.75mm pitch.
2” nosepiece
The 2” nosepiece screws into the T-mount adapter plate. The 2”
nosepiece allows the camera to be mounted in any 2” eyepiece
adapter. The 2” nosepiece is threaded to accept a standard
mounted 48mm filter.
1 ¼” nosepiece
The 1 ¼” nosepiece is optional and screws into the T-mount
adapter plate. The 1 ¼” nosepiece allows the camera to be
mounted in any 1 ¼” eyepiece adapter. The 1 ¼” nosepiece is
threaded to accept a standard 1 ¼” filter.
C-mount adapter
The C-mount adapter replaces the standard T-mount adapter on
the camera faceplate. The C-mount adapter is threaded with
standard C-mount threads, 1” x 32tpi. There are two different
versions of the C-mount adapter plate which provide the correct
focal depth for slim and mid-sized QSI 500 Series cameras. You
must use the correct version of the C-mount adapter plate for your
body style in order to achieve focus at infinity. A C-mount adapter
will mount to full-sized 500 Series WS model cameras but standard
C-mount lenses will not achieve focus at infinity.
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SLR lens adapter
SLR lens adapters are available for the following lens mounts:

Canon EF (EOS)

Nikon F
The SLR lens adapter provides the correct focal distance for specified lenses when
threaded to the standard T-mount adapter on full-size “ws” model cameras. Standard
extension tubes or T-mount extenders should be used to achieve the correct focal distance
with slim or mid-size bodies. Mid-size bodies will require a 0.5” extension tube. Slim bodies
require a 0.825” extension tube.
Liquid heat exchanger
The liquid heat exchanger (LHX) provides additional cooling of the
CCD beyond what can be achieved using the standard air cooling.
The liquid heat exchanger attaches to the back of the QSI 500
Series camera using four screws. Refer to the camera
specifications to determine the temperature differential that can
typically be maintained when using the LHX.
Recirculating pump
The recirculating pump is used to pump water through the liquid heat exchanger.
Color filter wheel
Cameras with an internal color filter wheel include one filter wheel
and an optional set of LRGB filters. Additional color filter wheels
can be ordered to hold 1.25” or unmounted 31mm filters. With
additional color filter wheels you can load a second set of filters,
such as narrowband filters or photometric filters, and easily replace
the entire filter wheel. See the Care & Maintenance section below
for instructions on removing and installing the color filter wheel.
See the WSG User Guide Supplement for details on accessories specific to WSG models.
See the Accessories page on the QSI web site for complete details on available
accessories: http://www.qsimaging.com/accessories.html
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7
Section
G U I D E
Care & Maintenance
Cleaning the exterior
The QSI 500 Series cameras are machined from military grade 6061 aluminum with a very
durable anodized finish that resists most scratches and fingerprints. Use a soft cloth to
remove dirt or spots from the exterior surface of the camera.
Installing or removing color filters
To change filters or replace the color filter wheel the front cover of the camera must be
removed. Place the camera face up on a stable surface. Using the included 3/32” Allen
wrench, carefully unscrew the 8 screws holding the camera faceplate to the camera back.
Lift the faceplate straight up to expose the color filter wheel.
Remove the color filter wheel by
unscrewing the screw in the center
of the filter wheel. Carefully lift out
the color filter wheel.
The standard color filter wheel
accepts 1 ¼” mounted filters. Any
filter can be screwed into any of
the 5 available positions.
To replace the color filter wheel a
slight pressure must be applied
with the outside O-ring against the
capstan motor that drives the color
filter wheel. Carefully line up the
center screw and press the filter
wheel O-ring gently against the
capstan motor. Lining up a filter or
empty filter position over the
shutter opening can help to achieve the proper alignment. When the screw is lined up
correctly it will screw in easily. Screw in the center screw until snug. No not over tighten.
Note:
Always remove the color filter wheel when installing or removing filters.
Take extra care to protect your filters anytime the front cover is off the camera.
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Installing or removing 31mm color filters
Some QSI 500 Series Color Filter Wheels are configured to hold unmounted 31mm filters.
Filter wheels capable of holding 31mm unmounted filters have a screw hole between each
filter position.
Note the retaining screws in the image above between each filter position which hold the
unmounted 31mm filters in place.
Different retaining screw/washer combinations are used to hold different thickness filters.
Filters up to 3mm thick (e.g. Astrodon, Astronomik) use the configuration shown above to
the left. 5mm thick IDAS filters use the configuration to the right.
Note:
A thin spacer or O-ring may be required to be placed under unmounted
filters that are less than 3.5mm thick in order to raise the top surface of the filter
above the top of the filter wheel recess so the retaining screw can hold the filter
firmly in place. The correct spacer should have been supplied with your filters or
filter wheel.
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Cleaning the color filters
As with any precision optical surface, the optical coatings or glass of color filters can be
permanently damaged by improper cleaning procedures. For best results follow the
cleaning instructions that came with your filters.
It is best to clean the filters infrequently and use the least intrusive of the methods below to
remove any dust or fingerprints.
1. Blow any dust off the filter with clean, dry compressed air.
2. Gently wipe off any remaining dust with a lens brush or microfiber cloth.
3. Remove the filter and clean it with gentle soap and water and then dry it gently
using a 100% cotton cloth.
Cleaning the CCD cover glass
As with any precision optical surface, the optical coatings or glass of CCD cover glass can
be permanently damaged by improper cleaning procedures. You are often better off not
trying to clean the CCD cover glass. The effects of small amounts of dust can be removed
from your images with proper calibration techniques.
If you must clean the CCD cover glass.
1. First try blowing off any dust off the filter with compressed air.
2. If that doesn’t work gently wipe off any remaining dust with a lens brush or
microfiber cloth.
Note: The CCD cover glass cannot be removed.
Updating the Firmware
QSI 500 Series cameras contain field-upgradeable firmware to control all camera functions.
QSI supplies a simple fail-safe Windows Updater application that handles all the details.
The Updater application is automatically installed from the Installation CD. It is also included
with the QSI USB Drivers and Software installer which can be downloaded from the QSI
web site.
Launch the Updater by clicking the Windows Start button and select "QSI > Updater". The
Updater window below will be displayed and the attached camera will go into a “listening”
mode waiting for new firmware to be loaded.
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If a single QSI camera is selected, its serial number will be shown in the “Select Camera”
pop-up menu. Click Refresh to scan for connected QSI cameras. If multiple cameras are
attached, select the camera you wish to update.
The Model, Firmware, Serial No. and Mfg Date fields will be updated to reflect the currently
selected camera.
Click the “Browse” button to select the new firmware file. The latest firmware files can be
downloaded from the Software page on the QSI web site. Firmware files are downloaded in
.zip format. The file will have to be unzipped before the Updater can load the new firmware
into the camera.
http://www.qsimaging.com/software.html
After a firmware file is selected, the “Update Firmware” button will be enabled. Click
“Update Firmware” to load the firmware into the camera. The status light on the back of the
camera will flash at varying rates while the firmware is loaded and then verified. When the
firmware has been loaded successfully, a dialog box will be presented.
Click OK. The Updater application will close and the camera will restart running the
updated firmware. Click “Help” on the main Updater window for additional details.
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Recharging the desiccant
The environmental chamber enclosing the CCD is filled with UHP argon during
manufacturing to increase cooling capability and prevent the formation of frost on the CCD
cover glass. This ultra dry and clean noble gas will generally remain in the environmental
chamber for about 3 years.
Warning:
Depending on specific use patterns and environmental conditions
around the camera, it is possible that moisture could build up in the chamber in
less than 3 years. Proper maintenance of the environmental chamber is critical to
the operation of the camera. If water vapor or ice forms inside the environmental
chamber when cooling below the dew point, it is critical that the camera be turned
off immediately and the instructions below followed to restore the camera to
proper operating condition.
You can restore many of the benefits of the original UHP argon by recharging the
microsieve desiccant in the desiccant chamber. The desiccant removes the moisture
present in the environmental chamber and stores it behind a submicron gas permeable
membrane. Over time the desiccant will lose its ability to remove additional moisture and
you may begin to see frost or dew forming on the CCD cover glass when operating the
CCD at low temperatures or in high humidity environments.
To recharge the desiccant, unplug the camera and allow sufficient time for the CCD to
reach room temperature. Place the camera, with the desiccant chamber cover upright, on a
stable surface. Loosen the four screws holding the desiccant cover and lift it from the
camera.
Lift the brass desiccant canister from
the camera. Preheat an oven to 500
degrees Fahrenheit. Place the
desiccant canister in the 500°F oven
for 4 to 5 hours. This will drive out the
accumulated water molecules,
recharging the desiccant.
Remove the desiccant canister from
the oven and let it cool. As soon as
the canister leaves the oven it will
begin absorbing moisture. To
minimize the impact on the
effectiveness of the desiccant, the
canister should be returned to the
camera as soon as it has cooled to
nearly room temperature. Place it
back in the desiccant chamber with
the fine grid face down toward the inside of the camera. Screw the nameplate back down
to the camera making sure that the O-ring surrounding the nameplate is carefully seated
against inside of the environmental chamber.
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Note:
Your camera can also be returned to QSI to have the environmental
chamber purged and refilled with UHP argon gas and the desiccant recharged.
Argon has better thermal insulating properties than air and provides the best
results but the camera will work extremely well in most conditions with just air in
the chamber and an active desiccant plug. Contact QSI Support for details.
Technical support
Most technical support questions can be answered 24 hours a day using the support
section of our web site at http://www.qsimaging.com/support.html. There you will find online
help and instruction manuals, technical articles and a searchable knowledge base with
answers to common questions. If you can’t find the answer to your question on our web
site please contact QSI technical support at shown below. Email is preferred.
Internet
http://www.qsimaging.com/support.html
Email
[email protected]
Phone
888-774-4223
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Appendix A – 500 Series Specifications
General Camera Specifications
Feature
QSI 500i Models
QSI 500s Models
QSI 500ws Models
Electronic Shutter
(Interline transfer CCDs only)
100µsec to 240 minutes
100µsec to 240 minutes
100µsec to 240 minutes
Mechanical Shutter
-
0.03 seconds to 240
minutes
0.03 seconds to 240 minutes
Internal Color Filter Wheel
No
No
Yes - 5 Position,
1.25" std filters
Camera Body Configuration
Slim
Enclosure
Medium
Enclosure
Full
Enclosure
Dimensions
W4.45”x H4.45” x D1.68” W4.45”x H4.45” x D2.00” W4.45” x H4.45” x D2.50”
(add 0.23" for T-Mount)
(add 0.23" for T-Mount)
(add 0.23" for T-Mount)
Weight, without Nosepiece
26 oz. / 740g
34 oz. / 950g
Optical Back Focus
(without Filters in path)
0.61" w/ T-mount adapter
0.68" w/ C-mount adapter
0.39" w/o mounting
adapter
0.90" w/ T-mount adapter 1.40" with T-mount adapter
0.68" w/ C-mount adapter 1.18" with C-mount adapter
0.68" w/o mounting
1.18" w/o mounting adapter
adapter
Thermoelectric CCD Cooling
Temperature regulation +/- 0.1°C, @ 0°C to -40°C CCD temperature
*In free air, Fans @ Full Speed
Typically 38°C below ambient air with 85% cooling power
*With Opt Liquid Cooling - Fans
Off
Typically 45°C below circulating liquid with 85% cooling power
(adds 0.75" to camera depth)
Cooling Fan Control
Intelligent, user configurable
Status and Notification
User configurable multi-color LED status indicator and multifunction audible beeper.
Over-temperature and high/low voltage alarms.
Power Consumption
12v, 1.5A (18 watts) at max cooling, max fans and filter moving
(25 AC watts max with included 90-240V AC power supply)
2.1mm i.d. DC power connector, o.d. 5.5mm, length 10mm, center positive
Operating Environment
Temperature: -20°C to 30°C, Humidity: 10% to 90% non-condensing
Computer Connectivity
USB 2.0 (USB 1.1 compatible)
Other Ports
Optically isolated 4 channel control port for telescope guiding or other application
specific control
T Mounting Adapter
Standard adapter - T-Thread, 42mm x 0.75mm
C Mounting Adapter
(1" x 32TPI)
Optional, C-Mount lens
focus compatible
(17.5mm backfocus)
Nosepiece
Standard, T-Adapter to 2" nosepiece
Optional, T-Adapter to 1.25" nosepiece
Optional, C-Mount lens
focus compatible
(17.5mm backfocus)
40 oz. / 1120g
Optional, for non-lens
adapters and accessories
(standard C-Mount lens
does not reach focus)
See the QSI 500 Series WSG User Guide Supplement for specifications on WSG models.
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Model 504 CCD Specifications
Feature
Standard
Optional
Optional
Model 532 CCD Options
Kodak KAF-0402ME
Kodak KAF-0402E
Kodak KAF-0401LE
CCD Architecture
Full Frame
Full Frame
Full Frame
Blue Enhanced
Yes
Yes
No
Microlens
Yes
No
No
No
No
Yes, 300x suppression
Imager Size: (WxH)
Anti-blooming
6.91mm x 4.6mm
6.91mm x 4.6mm
6.91mm x 4.6mm
Pixel Array (WxH):
784x520 total pixels,
768x512 active (visible)
784x520 total pixels,
768x512 active (visible)
784x520 total pixels,
768x512 active (visible)
Pixel Size:
9µm x 9µm
9µm x 9µm
9µm x 9µm
Typical Values
Pixel Full Well Depth
100,000 electrons
100,000 electrons
50,000 electrons
Quantum Efficiency
Peak: 83%
400nm: 44%
Peak: 73%
400nm: 30%
Peak: 35%
400nm: 20%
Pixel Dark Current
<1.0 electron per second at 0°C; <0.1 electron per second at -25°C
Dark Current Doubling
6.3° C
6.3° C
6.3° C
Intrinsic Read Noise
15 electrons RMS
15 electrons RMS
15 electrons RMS
Dynamic Range
76db
76db
70db
Charge Transfer Efficiency
>0.99999
>0.99999
>0.99999
Model 516 CCD Specifications
Feature
Standard
Optional
Optional
Model 516 CCD Options
Kodak KAF-1603ME
Kodak KAF-1603E
Kodak KAF-1602LE
CCD Architecture
Full Frame
Full Frame
Full Frame
Blue Enhanced
Yes
Yes
No
Microlens
Yes
No
No
Anti-blooming
No
No
Yes, 300x suppression
Imager Size: (WxH)
13.8mm x 9.2mm
13.8mm x 9.2mm
13.8mm x 9.2mm
Pixel Array (WxH):
1552x1032 total pixels,
1552x1032 total pixels,
1552x1032 total pixels,
1536x1024 active (visible) 1536x1024 active (visible) 1536x1024 active (visible)
Pixel Size:
9µm x 9µm
9µm x 9µm
Pixel Full Well Depth
100,000 electrons
100,000 electrons
50,000 electrons
Quantum Efficiency
Peak: 77%
400nm: 45%
Peak: 65%
400nm: 30%
Peak: 35%
400nm: 20%
9µm x 9µm
Typical Values
Pixel Dark Current
<1.0 electron per second at 0°C ; <0.1 electron per second at -25°C
Dark Current Doubling
6.3° C
6.3° C
6.3° C
Intrinsic Read Noise
15 electrons RMS
15 electrons RMS
15 electrons RMS
Dynamic Range
76db
76db
70db
Charge Transfer Efficiency
>0.99999
>0.99999
>0.99999
80
Model 532 CCD Specifications
Feature
Standard
Optional
Model 532 CCD Options
Kodak KAF-3200ME
Kodak KAF-3200E
CCD Architecture
Full Frame
Full Frame
Blue Enhanced
Yes
Yes
Microlens
Yes
No
No
No
Imager Size: (WxH)
Anti-blooming
14.85mm x 10.26mm
14.85mm x 10.26mm
Pixel Array (WxH):
2254x1510 total pixels,
2184x1472 active (visible)
2254x1510 total pixels,
2184x1472 active (visible)
Pixel Size:
6.8µm x 6.8µm
6.8µm x 6.8µm
Typical Values
Pixel Full Well Depth
55,000 electrons
55,000 electrons
Quantum Efficiency
Peak: 82%
400nm: 55%
Peak: 65%
400nm: 30%
Pixel Dark Current
<0.5 electron per second at 0°C ; <0.05 electron per second at -25°C
Dark Current Doubling
6° C
6° C
Intrinsic Read Noise
7 electrons RMS
7 electrons RMS
Dynamic Range
77db
77db
Charge Transfer Efficiency
>0.99999
>0.99999
Model 520 CCD Specifications
Feature
CCD Manufacturer & Model
520
Kodak KAI-2020M
CCD Architecture
Kodak KAI-2020CM
Interline Transfer
Microlens
Yes
Anti-blooming
Color Filters
520c
Yes - 100x suppression
Yes - Internal RGB on CCD; Bayer
color filter mask
No
Imager Size: (WxH)
11.84mm x 8.88mm
Pixel Array (WxH):
1640x1214 total pixels, 1600x1200 active (visible)
Pixel Size:
7.4µm x 7.4µm
Typical Values
Pixel Full Well Depth
Quantum Efficiency
45,000 electrons
Peak: 55%
400nm: 45%
Blue Peak: 42%, Green Peak: 36%,
Red Peak: 31%
Pixel Dark Current
<0.1 electron per second at 0°C
Intrinsic Read Noise
<8 electrons RMS
Dynamic Range
74db
Charge Transfer Efficiency
>0.99999
81
Model 540 CCD Specifications
Feature
CCD Manufacturer & Model
540
Kodak KAI-04022
CCD Architecture
540c
Kodak KAI-04022 (Color)
Interline Transfer
Microlens
Yes
Anti-blooming
Color Filters
Yes - 300x suppression
Yes - Internal RGB on CCD; Bayer
color filter mask
No
Imager Size: (WxH)
15.15mm x 15.15mm
Pixel Array (WxH):
2112x2072 total pixels, 2048x2048 active (visible)
Pixel Size:
7.4µm x 7.4µm
Typical Values
Pixel Full Well Depth
Absolute Quantum Efficiency
40,000 electrons
Peak: 55%
400nm: 45%
Blue Peak: 45%, Green Peak: 42%,
Red Peak: 35%
Pixel Dark Current
<0.1 electron per second at 0°C
Intrinsic Read Noise
<8 electrons RMS
Dynamic Range
74db
Charge Transfer Efficiency
>0.99999
Model 583 CCD Specifications
Feature
CCD Manufacturer & Model
583
Kodak KAF-8300
Kodak KAF-8300 (Color)
CCD Architecture
Full Frame
Microlens
Yes (Optional non-microlens version available)
Anti-blooming
Color Filters
583c
Yes - 1000x suppression
Yes - Internal RGB on CCD; Bayer
color filter mask
No
Imager Size: (WxH)
17.96mm x 13.52mm
Pixel Array (WxH):
3348x2574 total pixels, 3326x2504 active (visible)
Pixel Size:
5.4µm x 5.4µm
Typical Values
Pixel Full Well Depth
Absolute Quantum Efficiency
25,500 electrons
Peak: 56%
400nm: 38%
Blue Peak: 33%, Green Peak: 41%,
Red Peak: 33%
Pixel Dark Current
<0.02 electron per second at -10°C
Intrinsic Read Noise
8 electrons RMS
Dynamic Range
70db
Charge Transfer Efficiency
>0.999995
82
Appendix B – Warranty
QSI Warranty Policy
The limited warranty set forth below is provided by Quantum Scientific Imaging, Inc. for QSI
Scientific Cameras when purchased directly from QSI or an authorized QSI dealer within
the dealer's authorized territory. This limited warranty also covers the following accessories
if they were included with your original purchase: carrying case, AC power adapter, AC
cable, and USB cable.
Your QSI Scientific Camera is warranted against defects in materials or workmanship for a
period of one (1) year from the date of original purchase or longer in some regions as
required by law. QSI will, at its option, repair or replace any camera that is proven to be
defective during the warranty period.
This limited warranty covers all defects encountered in normal use of the QSI Scientific
Camera, and does not apply in the following cases:
(a) Loss of or damage to the QSI Scientific Camera due to abuse, mishandling, improper
packaging by you, alteration, accident, electrical current fluctuations, failure to follow
operating, maintenance or environmental instructions prescribed in QSI's User Guide or
services performed by someone other than QSI, or an authorized QSI Scientific Camera
Service Provider. Without limiting the foregoing, water damage, sand/corrosion damage,
dropping the camera, scratches, abrasions or damage to the body, internal parts or circuit
boards, or the imaging sensor will be presumed to have resulted from misuse, abuse or
failure to operate the QSI Scientific Camera as set forth in the operating instructions.
(b) Use of parts or supplies (other than those sold by QSI) that cause damage to the QSI
Scientific Camera or cause abnormally frequent service calls or service problems.
(c) If the camera body has been opened and any parts inside have been altered or
damaged, except for those parts that are expressly intended for user modification or
maintenance as described in the QSI Scientific Camera User Guide. QSI Scientific
Cameras have internal parts that should not be touched or modified by the user. UNLESS
SPECIFICALLY DIRECTED TO REMOVE THE CAMERA COVER, SUCH AS FOR
CHANGING FILTERS, WE STRONGLY RECOMMEND THAT YOU DO NOT OPEN
YOUR QSI SCIENTIFIC CAMERA BODY. QSI IS NOT RESPONSIBLE FOR DAMAGE
CAUSED BY MISUSE, ABUSE OR FAILURE TO OPERATE THE QSI SCIENTIFIC
CAMERA AS SET FORTH IN THE OPERATING INSTRUCTIONS.
(d) If the QSI Scientific Camera has had its serial number or dating altered or removed.
Manufacturer Warranties
Kodak provides a separate warranty that their CCDs will perform in normal use in
accordance to device specifications for a period of one year from date of shipment to the
customer. This warranty does not cover failure due to the following mechanical and
electrical causes after receipt of the device by the customer: Damage from mechanical
(scratches or breakage), electrical (ESD), or other misuse of the device (electrical, storage
temperature, etc.) beyond the stated maximum ratings in the device specifications.
Pelican® provides a lifetime unconditional warranty on all their cases.
83
Shipping Costs
The customer is responsible for all costs in shipping to QSI. QSI will pay shipping costs
when returning a product to the customer. All replacement/repaired products are shipped
via UPS Ground unless a rush is requested. The cost of such a shipping upgrade is to be
paid by the customer prior to shipment.
NO IMPLIED WARRANTY, INCLUDING ANY IMPLIED WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, APPLIES TO THE
QSI SCIENTIFIC CAMERA AFTER THE APPLICABLE PERIOD OF THE EXPRESS
LIMITED WARRANTY STATED ABOVE, AND NO OTHER EXPRESS WARRANTY OR
GUARANTY, EXCEPT AS MENTIONED ABOVE, GIVEN BY ANY PERSON OR ENTITY
WITH RESPECT TO THE QSI SCIENTIFIC CAMERA SHALL BIND QUANTUM
SCIENTIFIC IMAGING, INC. (SOME STATES AND PROVINCES DO NOT ALLOW
LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS, SO THE ABOVE
LIMITATION MAY NOT APPLY TO YOU.) QUANTUM SCIENTIFIC IMAGING SHALL
NOT BE LIABLE FOR LOSS OF REVENUES OR PROFITS, INCONVENIENCE,
EXPENSE FOR SUBSTITUTE EQUIPMENT OR SERVICE, STORAGE CHARGES,
LOSS OR CORRUPTION OF DATA, OR ANY OTHER SPECIAL, INCIDENTAL OR
CONSEQUENTIAL DAMAGES CAUSED BY THE USE OR MISUSE OF, OR INABILITY
TO USE, THE QSI SCIENTIFIC CAMERA, REGARDLESS OF THE LEGAL THEORY ON
WHICH THE CLAIM IS BASED, AND EVEN IF QUANTUM SCIENTIFIC IMAGING HAS
BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. IN NO EVENT SHALL
RECOVERY OF ANY KIND AGAINST QUANTUM SCIENTIFIC IMAGING BE GREATER
IN AMOUNT THAN THE PURCHASE PRICE OF THE QSI SCIENTIFIC CAMERA SOLD
BY QUANTUM SCIENTIFIC IMAGING AND CAUSING THE ALLEGED DAMAGE.
WITHOUT LIMITING THE FOREGOING, YOU ASSUME ALL RISK AND LIABILITY FOR
LOSS, DAMAGE OR INJURY TO YOU AND YOUR PROPERTY AND TO OTHERS AND
THEIR PROPERTY ARISING OUT OF USE OR MISUSE OF, OR INABILITY TO USE,
THE QSI SCIENTIFIC CAMERA NOT CAUSED DIRECTLY BY THE NEGLIGENCE OF
QUANTUM SCIENTIFIC IMAGING. (SOME STATES AND PROVINCES DO NOT ALLOW
THE EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES,
SO THE ABOVE EXCLUSION OR LIMITATION MAY NOT APPLY TO YOU.) THIS
LIMITED WARRANTY SHALL NOT EXTEND TO ANYONE OTHER THAN THE
ORIGINAL PURCHASER OF THE QSI SCIENTIFIC CAMERA, OR THE PERSON FOR
WHOM IT WAS PURCHASED AS A GIFT, AND STATES YOUR EXCLUSIVE REMEDY.
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