User manual | Buying Guide to Projectors

Projectors
http://www.projectorcentral.com/
Buying Guide to Projectors
By Timothy McDougal
As with so many consumer products these days, selecting a projector can be daunting,
since there are just so many options. However, choosing the right projector is pretty
simple as long as you can supply three pieces of information:
1. The screen size (width, most importantly).
2. Distance between the projector and the screen (throw distance).
3. An estimate of the amount of ambient light present in the room in which the projector will be used.
At this point you might be thinking, “Great. But I can't answer any of those
questions." Or, "I plan to take my projector on the road and could be using it
anywhere." Often, with a little forethought, the “I don't know” can be whittled down
to a fairly good educated guess. If not, you are not completely out of luck. In
addressing each topic, we will suggest your best bet when confronted with unknowns.
What is a projector?
A projector may be best thought of as an inverted camera, spitting light out of a lens
rather than receiving it. For the sake of this buying guide, we will be considering
digital projectors—that is, projectors with video inputs that serve a similar function to
a TV or computer monitor while offering a number of benefits, including the ability to
produce much larger image sizes and easy portability. The principles I will outline
below apply to all types of projectors. However, it will help to start by dividing digital
projectors into four categories:
1. Pocket, also called "pico"
2. Home theater
3. Multimedia
4. Large venue and fixed installation (a subset of multimedia)
Obviously there will be overlap, and not all models will fit easily into a particular
category. For example, home theater and multimedia projectors are very similar. In
most cases, it will be clear from your application which type you need. Boardroom
presentations: this will be multimedia. In a living room: home theater. For a lecture
hall, seating 500 people: large venue. Ultra-portable, where a small screen size is
acceptable: pocket or pico projector.
Pocket projectors
Pocket projectors are still a relatively new technology. Although most would require a
fairly large pocket, they are small enough to hold in your hand, and usually can be
mounted on a tabletop tripod as well. Because they use LED lamps, they aren’t very
bright: 20 to 1,000 lumens. In comparison, multimedia projectors typically range from
2,500 to 4,500 lumens (higher if we included fixed installation). This makes them
useful as an alternative to carrying a monitor or TV around, but they won't really cut it
if your intention is to present to a group of more than a few people. Until recently,
pocket projectors have been regarded as more of a novelty—a fun consumer item—
than a serious display technology. However, as LED lamps improved, the capabilities
of pico projectors have increased and they are starting to encroach upon the portable
segment of the multimedia projector market.
Another notable limitation common to pocket projectors is the lack of a zoom lens.
This means that the only way you can control image size is by physically moving the
projector closer or farther away from the screen. If you favor compact form factor
over brightness and zoom, a pico may be right for you. If not, you are probably a
candidate for a multimedia projector.
Multimedia projectors
Multimedia projectors represent the largest category, and are the most widely sold at
B&H (close to 800 models, currently). Multimedia projectors are general purpose, and
are used for everything from giving PowerPoint presentations to screening video clips
and slideshows at weddings. They are typically considered portable, weighing from 3
pounds for the ultra-slim models and going up from there, and their brightness ranges
from 2,500 to 4,500 lumens or so. Apart from the special sub-category of short-throw,
they virtually always have zoom lenses. However, the zoom range is usually shorter
than that of their home theater counterparts: 1.2x to 1.5x (compared to 2x in the
home-theater realm). This means special care needs to be taken when choosing, to
make sure the screen size is compatible with the projector's throw ratio. Multimedia
projectors virtually always have VGA and composite video inputs, and most models
now feature HDMI as well. In some cases, a DVI-D port will be provided instead of
HDMI, but an HDMI device can still be connected using an inexpensive adapter.
Similarly, DVI devices can be connected to a projector with only HDMI using a DVI
to HDMI cable or adapter.
Common resolutions for multimedia projectors are SVGA (800 x 600), XGA (1024 x
768), WXGA (1280 x 800), and WUXGA (1920 x 1200), though 4K is just over the
horizon. The most popular resolution is XGA, and is generally suitable for
PowerPoint presentations—but, because it is a 4:3 format, may not be ideal if you
plan to screen high definition.
Short throw projectors
"They are typically wall rather than ceiling mounted, and are
designed to be installed very close to the screen: 18 inches to 2
feet."
Although most multimedia projectors have a built-in zoom lens, an important
subcategory is short throw and ultra-short throw. Generally, a throw ratio of less than
1:1 is considered short throw. The most common throw ratios are 0.5:1 and 0.3:1, with
the latter fulfilling the distinction of being "ultra-short throw." Short throw projectors
almost never have zoom lenses, and in many cases they use a mirror onto which the
image is projected first, before being reflected at the screen. They are typically wall
rather than ceiling mounted, and are designed to be installed very close to the screen:
18 inches to 2 feet. Short throw projectors are most often used in classrooms, and are
ideal for pairing with digital whiteboards. One might be tempted to place a short
throw projector further back than the recommended couple of feet, as a way to
achieve a very large image in a small space (assuming sufficiently low ambient light
levels, of course). This probably won't work, since short throw projectors keystone
severely when used outside their recommend throw distance range, and will require
some very creative mounting to produce an undistorted image. Because they are
meant for smaller screen sizes (8 feet wide or less), short throw projectors normally
top out at 3,000 lumens. If you need a brighter projector and have limited space, you
will need to look at a fixed installation projector with interchangeable lenses instead.
Home theater projectors
True home theater projectors—as opposed to multimedia/home theater crossovers,
which from a feature perspective can be treated as multimedia projectors—place the
emphasis on image quality above all else. They rarely get brighter than 2,500 lumens
(though this seems to be changing), and have the most zoom of any projector type that
uses built-in lenses. They are intended for use in a living room, or perhaps small
screening room, where the ambient light can be controlled completely. They use either
DLP or LCoS imaging technology, almost never three LCD, and will generally give
you the best-looking picture of all types, assuming you use them in complete darkness
and at a sensible throw distance.
Home theater projectors often feature low-voltage control (LVC), so that turning the
projector on or off can trigger the screen to rise or descend, or open and close if it is a
fixed frame covered by drapes. To achieve the quietest possible operation, they have
more efficient—or more elaborate—cooling systems, making them relatively bulky
and, in some cases, unable to support inverted installation. They are also the most
expensive type of projector, relative to specifications. Virtually all are Full HD or 4K
(true DCI 4096 x 2160 4K, in fact). Be careful, though. Companies often lump what
are essentially restyled multimedia projectors into the home theater category. Telltale
signs are high lumen ratings (more than 3,000 lumens), VESA rather than HD video
native resolutions (such as WXGA and WUXGA), and zoom that's shorter than 2x.
If you want a great picture, can block out all ambient light, and are working with a
screen size of up to 100 inches or so, home theater projectors are a great choice.
Otherwise, you may have to consider a brighter multimedia projector, even if you plan
to use it in a home theater setting.
Fixed installation and large venue
Fixed installation and large venue projectors are often included together with
multimedia projectors. They are the brightest type available in the consumer market,
starting at around 4,500 lumens and going up to 20,000 or more. Installation
projectors are not generally considered portable, and take time to set up. In most
cases, they feature interchangeable-lens systems, making them the most adaptable in
terms of throw distance. They are normally used in lecture halls, movie theaters,
houses of worship, stadiums, and other similar settings that require screening for large
groups. In addition to large screen sizes, they are used in settings where ambient light
can't be controlled. Many also support stacking, meaning the output from two or more
projectors can be aggregated to increase the brightness beyond what a single projector
can achieve.
Because of their weight and the nature of the lens systems they use, in most cases,
installation projectors should be specced out by an integrator, and require installation
by a professional.
Now we come to implementing the three pieces of information mentioned earlier.
Why do screen size and throw distance matter? Or: What is
throw ratio?
Projectors have a very important specification called "throw ratio". Throw ratio is a
specification that is determined by the first two pieces of information in the equation:
1. How far the projector is from the screen (throw distance)
2. How wide the screen is
For example, if your screen is 10 feet wide and the projector is 15 feet away, you will
need a lens that covers a throw ratio of 1.5:1.
The first step in choosing a projector, therefore, is pinning down how wide the screen
is and how far it can be placed from the screen—once you've done this, your choices
will narrow considerably. Of course, you may have flexibility. Maybe your space
allows you to mount the projector anywhere you want on the ceiling. In this case,
while you might technically be able to choose any projector you want, you should
consider mounting the projector as close to the screen as you comfortably can. Light
is subject to the Inverse Square Law, meaning brightness drops logarithmically with
increased distance, so the closer you can mount it, the fewer lumens you will need. At
the other extreme is a case where you have an existing mount installed on the ceiling
that you want to reuse. In this case, you will need to find a projector that features the
exact throw ratio dictated by the position of the mount relative to the width of the
screen.
Short Throw
Medium Throw
Long Throw
Screen Size
Projector screens merit a whole buying guide of their own. However, at this point, many of you will be understandably
wondering, "If I'm starting from scratch, how should I know what screen size to get?" A quick, and very rough, rule of
thumb is to multiply the distance of the "least-favored viewer"—i.e., the person farthest from the screen—by 1/5. So, if
your LFV will be sitting 50 feet away, you'll need a screen that is 10 feet high.
But what if you don't know? Or what if the projector is being used on the go? Every
effort should be made to find out, since there is no “standard” throw ratio, nor is there
a standard screen size. On paper, multimedia projectors with built-in lenses don't
appear to vary a ton. They mostly range from somewhere between 1.3:1 to 3:1,
whereas a fixed installation projector with interchangeable lenses might have lens
options ranging from 0.8:1 up to 15:1. You might have decided, since they're all about
the same, to risk it. This might work, but remember that even exceeding only a foot on
a 10-foot screen can lead to a critical part of the presentation being cut off.
If you really can't find out, you have two options: spring for a model with more
zoom—which will cost more—or err on the side of shorter throw. Not true short
throw, mind you—those don't have zoom and they keystone excessively if not
carefully positioned. But something closer to the 1.3:1 end of the spectrum. Why?
Because more often than not, getting the projector closer to the screen will be less of a
problem than getting it farther away.
Finally, keep in mind, throw is based on native aspect ratio. If, for some reason, you
are setting the projector to a narrower aspect ratio than native, the projector will
effectively have a longer throw.
Where does a projector's light originate?
Projectors mainly use two lamp technologies: LED and metal halide. LED projectors
top out at around 1,000 lumens right now, and mostly fall into the pico category.
Almost all of the rest use metal halide—the classic digital projector lamp, lasting
between 2,000 and 5,000 hours on. There are also a few eccentric projector models
that feature a green laser/LED hybrid system.
How much brightness do I need?
While throw ratio is very important, brightness is the most important specification to
get right. And this is where the third piece of information I mentioned—amount of
ambient light—fits in. If the image isn’t bright enough to be seen clearly, all other
considerations fly out the window. Getting enough light out of a projector is often the
biggest challenge, but remember, it is nearly impossible to get a projector that is too
bright. If a projector is ever "too bright" you can always just turn the brightness down.
But making a projector that is too dim brighter... good luck!
Ambient light competes with the projector's output, causing the image to get washed out.
In the ideal world in which we don't live, projectors would always be used in total
darkness. The more light you add, the more you lower contrast and wash out the
image. Even getting a brighter projector only solves the problem partially, since
ambient light is mixing with the darker parts of the image, making them cloudy. If
you have to use a projector in ambient light, you will never get a perfect image, but it
is possible to at least get a viewable image.
Projector brightness is measured in ANSI lumens (lumens for short). Calculating how
many lumens you need requires knowing the throw distance, image width, how much
ambient light is present in the room, and the content that will be shown. The simplest
way to figure this out is to use a projection calculator, a software tool that crunches
the number for you. Many projector manufacturers provide calculators on their
websites. If not, Projector Central is a great resource, and offersprojection
calculators for nearly every projector model made.
Here are some examples of numbers of lumens you should anticipate needing:
•
A living room where the lights can be turned off completely: 1,500 to 2,000 lumens
•
A school classroom or boardroom where the lights can be dimmed, if not fully extinguished: 3,000
lumens
•
A lecture hall or small church requiring a 10-foot-wide screen, and has a moderate amount of light: 5,000
lumens
•
A movie theater: 20,000 lumens or more
After looking at the calculator, you may have noticed brightness is measured in footcandles. Without a light meter, how is one supposed to know how many foot-candles
of light a room has? Here, a bit of judgment and common sense come into play.
Would you consider it "well lit" (50 foot-candles), moderately lit (20 foot-candles), or
dimly lit (less than 5 foot-candles)? Or is there bright sunlight blazing in? If the
installation is for critical view, then I would recommend getting a light meter, and
carefully measuring. But for most practical everyday uses, a rough guess-timate erring
on the side of too bright should suffice.
"If you legitimately don't know where the projector will be used,
then get the brightest you can afford that you are able to carry
around."
The content should also be factored in. Are you projecting white song lyrics over a
solid background? Or are you showing photographs in an art gallery? In the former
case, the contrast of the image is so high you can get away with a much weaker
projector. In the latter case, you probably want to preserve every tonal nuance you can
and, so, will need more lumens.
If you legitimately don't know where the projector will be used, then get the brightest
you can afford that you are able to carry around. However, chances are, with a bit of
thought you can come up with a reasonable estimate of the setting. For example, if
you are a traveling product rep conducting trainings with groups of up to 20 people at
various companies, 3,000 lumens may be enough as long as you don't encounter
windows without blinds. If you do have a room without blinds, or are trying to project
outdoors in daylight, be aware: no projector may be bright enough. You're asking the
projector to do something it simply wasn't made to do.
Finally, if the projector is being used for any kind of critical viewing, then it is
imperative that ambient light be eliminated from the setting. If this isn't possible, then
TVs or monitors (perhaps arranged as a "video wall") should be used as an alternative.
Ambient light not only degrades the image but also alters it, potentially undoing any
careful calibration of the projector or color-correction work on the image itself.
Projectors probably aren't ideal for critical viewing to begin with, but especially not
when there is light in the room.
If you can't find a single projector that is bright enough, you might consider stacking.
Stacking requires a compatible projector or using outboard hardware so the images
can be aligned perfectly.
Now that you know the throw ratio and brightness, you can consider secondary
factors, such as resolution and contrast ratio.
What resolution do I need?
Resolution matters, but perhaps less than you might think. Most projectors these days
are least XGA (1024 x 768) resolution, a 4:3 aspect ratio format that has been the
longtime staple for giving PowerPoint presentations. A few entry-level models are
still SVGA (800 x 600), and pocket projectors sometimes have funky, low native
resolutions that the manufacturers are coy about admitting. Because of high-definition
video, increasingly widescreen formats, starting at WXGA (1280 x 800), are
supplanting the legacy 4:3 standards.
Personally, I would not recommend going lower than XGA. At SVGA and lower
resolutions, pixelation in the image will be very apparent. Also, many computer
programs require at least XGA resolution even to run. You can cheat and set the
computer's projector output to XGA, and let the projector scale the image down to its
native resolution; however, the image will look blurry and smaller text will be
unreadable. If you ever used a scan converter to hook your computer up to standarddefinition TV you'll know what I'm talking about. The so called “screen-door effect”
(discussed below) will also be worse in SVGA or lower.
In home theater setups, the screen-size-to-viewer distance ratio is a lot smaller than
for other applications—here a higher-res image pays off. Otherwise, XGA is probably
fine as a baseline, though going higher never hurts. Ideally, I would recommend
starting at WXGA and going up from there. Even if you are PowerPoint user,
bumping up to 16:10 won't really hurt, plus, you'll be ready if you want to screen HD
video down the road. For special applications, such as exhibiting photos, you will
want higher resolution: at least 1600 x 1200 (UXGA) for 4:3 or 1920 x 1200 for 16:10
(WUXGA), if not better. In the case of home theater, it's really a question of whether
to invest in 4K or not, since nearly all home theater projectors are at least Full HD
(1920 x 1080) anyway. Certainly 4K in a projector makes more sense than 4K in a
TV, since you can achieve a larger image size. But right now there are few sources for
4K content, unless you buy a camera and record it for yourself. Also, HDMI 1.4a only
supports 4Kp30 (i.e., maxes out at 30 frames per second / 30Hz for computer
sources), so you if you early-adopt with the intention of "future proofing" you may
end up kicking yourself down the road when HDMI 2.0 comes out and adds support
for higher frame rates.
If you really want to be scientific about resolution, a quick Internet search will turn up
a number of resolution calculators where you can plug in a screen size and viewing
distance and the calculator will spit back a resolution. These are great, but, as with
brightness, the content really needs to be factored in, and a calculator can't do that. A
highly compressed YouTube video may look like hot garbage no matter what you try
to show it on. On the other hand, if you are putting together a screening room for a
production company, 4K may barely cut it.
Should I care about contrast ratio?
Contrast ratio is probably the most meaningless spec you'll find. Like HDTVs,
projectors rely on so-called “dynamic contrast” to boost their on-paper performance.
Also, the screen surface plays an import role in contrast. Finally, any ambient light
will bring contrast ratio down into the double digits. Unless you have optimal viewing
conditions (i.e., next to no light and a good screen), a 500:1 contrast ration and a
100,000:1 contrast ratio on paper probably won't render a visible difference.
What are keystone correction and lens shift?
Most projectors will have at least vertical, if not horizontal keystone correction; some
even offer lens shift. Of course, we are all familiar with the trapezoidal “keystone
effect”—the image appears wider at the top when the projector is too low, or wider on
one side when the projector is horizontally off center. Keystone correction remedies
this, up to a certain specified percentage. The problem with keystone correction is that
it is achieved digitally, like digital zoom on a camcorder. The more you apply, the
more the image will be degraded. As long as you mount or place the projector so that
the lens is not below the bottom of the screen or above the top of the screen (assuming
a right angle relative to the screen) you should be okay. If you starting getting outside
of a normal mounting situation, or are staking or edge blending, you will seriously
want to consider picking a projector with lens shift. Lens shift serves the same
purpose, and then some, and achieves it optically with not loss in image quality. To
get lens shift you are probably looking at a high-end home theater or fixed installation
projector.
Original Image
Vertical Keystone
Horizontal Keystone
DLP vs LCD: Which is better?
DLP is for better image quality, LCD lasts longer. Next topic.
Just kidding!
There are three imaging systems used in most projectors today: DLP, LCD, and one
you might not have heard of: LCoS. Between the DLP and LCD it is really a toss-up
these days. LCD has a little less rainbow effect on average; DLP a little less screendown effect. Apart from that, LCD has a slight reliability edge in that there are no
moving parts in the imaging system, whereas single-chip DLP uses a spinning color
wheel and micro mirrors. LCD panels can still fail, but more often it is a case of dead
pixels rather than a catastrophic failure as when a DLP color wheel stops working. If
you are using the projector in a remote setting where it can't readily be replaced or
served, then go LCD. Otherwise LCD vs DLP doesn't need to be a deciding factor.
Sample of Screen-Down Effect
In some ways, the underdog, LCoS, offers the best of both worlds. Some of you may
vaguely recall HD projection TVs that had LCoS. LCoS (Liquid Crystal on Silicone)
is a reflective technology like DLP, but in this case, the light is reflected from a
silicone-backed LCD panel rather than micro mirrors. This system currently claims to
produce the least screen-door effect and, because it is LCD, is free from the rainbow
effect and other color-wheel-related artifacts. It is used almost exclusively in high-end
multimedia projectors targeting critical viewing applications. On Sony home theater
projectors, LCoS is called SXRD (Silicon X-tal Reflective Display).
What connectivity do I need?
In terms of video inputs, all but very high-end professional systems have more or less
the same options: VGA, composite, component (usually on the VGA connector),
HDMI, and occasionally S-Video. VGA has been on projectors forever, and because it
is so widely used in many existing AV systems, will remain an option for some
time—we just can't seem to kill it. Otherwise, HDMI is the main connector to look
for, now and in the near future. Most computers can be adapted to HDMI with
inexpensive passive adapters if they don't already have a built-in HDMI output. So
look for HDMI, first and foremost. In some cases, a projector will have a DisplayPort
or DVI input instead of HDMI. As long as you're not trying to pass 4K, these inputs
can be adapted to accept an HDMI signal, again, using a passive adapter or cable. On
professional projectors, you will also sometimes find SDI (serial digital interface), a
digital interface mainly used in the broadcast world—at this level, you can often
install expansion boards to customize the projector's connectivity, tailoring it to your
specific needs.
2 HDMI Adaptors. Usually to connect to a video source to a display, includes
computers, but mostly for Digital TV.
1. VGA and DVI Graphics Adapters. Usually to connect to
displays from computers. More on these later.
One tip for installations: do not run HDMI more than 25 feet. There are HDMI cables
that are longer, but the longer you go, the more the cable acts as an antenna, picking
up RF signals. For whatever reason, 25 feet seems to be where reliability dives off the
cliff. If you need to send HDMI farther, you can use baluns,special converter boxes
that modify the signal so it can travel over a balanced (i.e., interference-resistant) type
of cable, most often Ethernet.
In addition to video, many multimedia and home theater projectors have some form of
wired control port, usually RS-232. This allows integration with automation systems
or control using custom-developed software. Increasingly, Ethernet is becoming a
standard feature, and will typically allow you to operate the projector across a
network, or even the Internet, using any web browser. Some also have Wi-Fi
capability.
Multimedia projectors often have one or more USB ports, though figuring out
what the USB port does isn't always easy. Possible USB functions include:
•
A video interface—as an alternative to using VGA or HDMI
•
Plugging in a presentation mouse
•
A port for a USB flash drive for giving "PC-less" presentations
•
Connector for an optional Wi-Fi dongle
•
Remote controlling the projector from a computer
PC-less presentation is probably the most-demanded feature of a USB port, and it is
becoming increasingly common. However, in most cases this feature is for still-image
formats, such as JPG only. The projector will not act as a media player and play video
files. Some projectors also include software for converting PowerPoint presentations,
but this can be buggy; I would recommend exporting your slide shows directly from
PowerPoint to a supported still-image format such as JPG instead. You will lose
animation effects, but at least it is reliable. Pico and home theater projectors, on the
other hand, often have built-in media players so you can play back video from a USB
device or even a memory card.
Wireless video is one of the most asked-for inputs. Some projectors have it, usually in
the form of an optional USB dongle. But, because the video generally has to be
compressed and, due to the presence of so many competing wireless devices—
especially wireless routers—the wireless interface on projectors is only recommended
for PowerPoint, photos, or showing relatively static computer graphics, not for fullframe-rate video. In addition, the range of projector wireless dongles is usually limited
to about a 30-foot line of sight. If you really need to send video wirelessly, there are
third-party options that can do it, and some are even uncompressed. But even with
dedicated solutions, there are so many unpredictable environmental variables that the
technology is not going to be mission-critical reliable.
Can I rely on a projector's built-in speakers?
“Speccing” a projector based on its speakers is a bit like “speccing” a car on how well
it works as a boat. Projector speakers are terrible, even worse than TV speakers. Many
will de-embed audio from the HDMI stream, so you might be tempted to just plug
your speakers directly into the projector. Unfortunately, they often don't even extract
audio very well. I would recommend you use separate speakers if your application
includes sound, and that you plug the computer, DVD player, or other video source
directly into the speakers or sound system, bypassing the projector itself. Most devices
have separate audio outputs in addition to the video output.
If you have to rely on the built-in speaker, then be sure to pick a projector that puts
out at least 10 watts.
Is 3D still "a thing?"
Consumer electronics manufacturers openly admit they've given up on 3D. You might
still want 3D. If so, you'll probably need to look for a home theater projector. Many
multimedia projectors purport to be "3D-ready;" in most cases, they only work with
computers that have compatible graphics cards (DLP-Link is one proprietary
technology that is widely used). Home theater projectors are more likely to feature
HDMI 3D support so you can use them with Blu-ray players. When speccing for 3D,
keep in mind that you are effectively cutting the brightness in half. As an alternative
to buying a 3D-ready projector, you can also use a combination of two-projector
stacking and polarizing filters. A special processor is required to demux the left- and
right-eye streams from the HDMI signal.
Conclusion: Where does image quality come from?
Chances are, you want the best picture quality for your money, and it probably seems
like we've been avoiding the question, speaking instead about boring, if important,
practicalities like throw ratio and lumens. To this complaint, there are two arguments:
1. If the projector you choose isn't bright enough, the image quality will suffer, regardless. And if it throws
an image the wrong size, the viewing experience will suffer.
2. Image quality is difficult to measure to the extent it can be measured objectively at all. And a lot of
"image quality" is just plain subjective.
Regarding argument 1, I'm sure you'll agree I've said enough already. Addressing
number 2:
If you know what brightness and throw ratio you need, I would suggest to you that
two projectors with comparable specs at a similar price point will perform almost
exactly the same. Flipping a coin may not sound like the most sane way to make a
purchasing decision, but once you've determined what features are mandatory, and
settled on a price point, you've already done everything you can to make a smart
choice, Whether the preceding steps have narrowed your options down to one model
or ten, rest assured, whatever you pick from those that remain will be the best choice
for you.
The Takeaway
•
Is a projector the right choice? If you need to achieve a larger screen size and/or if portability is key, then
yes.
•
When not to use a projector: Projectors are for screening. They should not be used for color correction
work or critical evaluation. Additionally, they work best in low light. If you have bright, uncontrollable
ambient light, especially sunlight, then consider an alternative.
•
Once you know the screen size, determine the throw ratio based on the screen width and the distance
between the projector and the screen.
•
If the screen size isn't known in advance, opt for a projector with more zoom or one that has a shorter
throw. In most cases, getting closer is easier than getting farther back.
•
Taking into account the screen size, throw distance, and the amount of ambient light in the room, use a
projection calculator to determine the necessary minimum brightness in lumens.
•
If you cannot calculate the brightness you need, consider the brightest projector you can get, within
reason.
•
Factoring in the content you will be showing and the distance of your average audience member,
determine the minimum resolution you need. WXGA is usually safe for multi, though going up to 1080p
and beyond certainly isn't going to hurt (except maybe your pocket book). For home theater, you will
always want 1080p; and may even want to consider 4K.
•
Consider any secondary features you may need, such as the ability to show a presentation from a USB
flash drive.
•
Don't sweat it if, after the above process of elimination, your search turns up too many choices—chances
are any will work fine for you.

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