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Flourescent
photo &
video
On the Rise
Night Diving
Edited by Don Silcock
Text and photos by Steffen Beyer
Fluorescence night dives, or
fluoro, UV and glow dives,
as they are also known, are
becoming increasingly popular as more and more dive
centres offer scuba divers and
underwater photographers
the chance to experience this
unique underwater phenomenon.
There are also an increasing number
of vendors offering diving equipment
for use on these special dives, and the
purpose of this article is to explain the
basics, background, techniques and
equipment associated with this interesting aspect of the underwater world.
The basics—what is it?
Fluorescence is the capability of certain
materials to absorb light transmitted
on one wavelength and then emit it
again nanoseconds later on a different
wavelength. The phenomenon occurs in
certain living organisms, various minerals
and in petrified fossils.
Fluorescence should not be confused
with either phosphorescence, which is
the capability to store light and then
emit again over time such as on the dials
of our diving gear or watches, or bioluminescence where light is produced
by living organisms when they consume
energy.
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Underwater fluorescence is usually
identified with green, and indeed it is the
most common colour for reasons that will
be explained, but it is also possible to see
red, orange and yellow fluorescence.
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The background
—Once upon a time in Torbay…
The fluorescence phenomena is believed
to have been first discovered in marine
creatures back in 1927 when a certain
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Charles E.S. Phillips noticed some glowing
anemones in a tidal pool on the beach
at Torbay, in the southwest of England.
The bright green colour they were emitting caught his eye, and he took some
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samples back to his laboratory where he
used a light source together with a filter
called “Wood’s Glass“, which absorbs visible light but allows ultraviolet light to pass
through, to establish that the anemones
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Flourescent
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silver
Fluorescence
schematic (right);
Red fluorescing
anemone in daylight (far right)
were in fact fluorescent.
Then in the 1930s, the Japanese
marine biologist Siro Kawaguti established that the most common coral
pigments also in marine creatures fluoresced in green, followed in 1955 when
those pigments were first described and
formally recognised as a protein—coining the name “Green Fluorescent Protein” or GFP.
During the late 1950s, as more people
started to scuba dive, the phenomena
became more widely known, and articles
started to appear in publications such
as Skindiver and National Geographic
showing the use of “blacklight” ultraviolet
underwater torches to observe it.
In 1963, Sir Arthur C. Clarke, the
renowned author and diver, further
popularised the phenomenon when he
described his experiences with fluorescence in his science fiction novel Dolphin Island.
Probably the most
well-known example
of fluorescence from
those early days, and
one which still puzzles
many to this day, are
bright red anemones at depths well
beyond where the
Sea urchin (above) and scorpionfish (center) show fluorescent properties
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colour has completely disappeared from the
visible spectrum.
Just ask any
underwater photographer about
the puzzling
results from their
efforts to capture an image of
such anemones.
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Ultraviolet and blue light 101
While it is possible to see fluorescence
underwater during the day, it really is at
its eerie best after dark, but you will need
a light source to stimulate those proteins! For many years ultraviolet (UV), or
“blacklight”—light which in not visible to
the human eye because of its relatively
high frequency—has been synonymous
with viewing fluorescence, largely as a
result of the work done by Dr Rene Catala in the late 1950s at New Caledonia’s
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Noumea Aquarium.
But in the early 1990s, research by Dr
Charles Mazel in the cold waters of Massachusetts and the warmer climes of the
Bahamas, established that blue light was
much better than UV. What Mazel found
was that blue light (high energy visible
light with a frequency between 400 and
500nm) was much more effective at
exciting those proteins to fluoresce, and
he went on to start a company called
NightSea in 1999, which manufactures
equipment for viewing and photographing fluorescence—be it underwater or in
the laboratory.
Although much more efficient than
ultraviolet, there is a downside to using
blue light, as the fluorescence has to be
viewed through a yellow barrier filter to
block out the blue light reflected back
to you, which tends to overwhelm the
actual fluorescence. Plus high energy visible light has been linked to age-related
macular degeneration.
The yellow filter is mounted on the face
mask and basically makes it safe to view
the blue light induced fluorescence,
while greatly enhancing the overall
experience—you can see much more
fluorescence with the filter than without
it.
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cinema of dreams
www. seacam.com
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Anemones fluorescing (right);
Brain coral fluorescing (lower
left)
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Why is the fluorescence there?
Fluorescence occurs in many marine
organisms such as coral, tunicates,
barnacles, sponges, anemones, jellyfish, clams, nudibranchs, cephalo-
pods, shrimp, crabs, worms and fish—
to name but a few. It also is found in
some fresh water organisms, and it
seems obvious that the phenomenon
must provide some form of benefit to
all those creatures, but unfortunately
research into what benefit this might
be is still in its infancy.
However, there are some preliminary
hypotheses and findings, one of which
is that some studies suggest that fluorescence in corals may act as a form
of sunscreen by protecting the corals and their symbiotic algae against
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harmful UV radiation.
Another hypothesis states that fluorescence allows corals to transform the
only light available to them, namely
blue light, into such wavelengths as
can be used by
their symbiotic
algae for photosynthesis, allowing the corals to
dwell successfully
at greater depths
than their competitors without
such a capability
can, giving them
an evolutionary
advantage to survival.
Yet another is
that fluorescence
in reef fish may
help them to visually merge with
their coral backgrounds so as to
make less conspicuous to predators.
And a recently
published study
shows that the
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Flourescent
is now available!
health of corals correlates with their
fluorescence, which means that the
latter can be used as a measure of the
former.
Photographing fluorescence
To photograph fluorescence underwater a normal camera and strobe is
Feather star fluorescing
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Shoot-Out 2012 competition album
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used, but two additional special filters
are required—one on the strobe and
the other on the camera. The strobe
filter converts the normal white light
output in to one of intense blue light,
which stimulates the fluorescence and
allows it to be photographed.
While the one on the camera is a
yellow filter, which allows the sensor
to record the image in the same way
the barrier filter allows the human eye
to view the blue light induced fluorescence.
Once suitably equipped, the physical logistics of night time fluoro-photography need to be given some
thought. Specifically, you will need a
traditional white light source to find
your way around the actual site and a
blue light one to initially stimulate the
fluorescence so it is visible.
Prior to switching light sources the
yellow barrier filter on your mask needs
to be in place so that you can see the
fluorescence properly, but once the
filter is in place that is all you can see
and everything else is pitch black.
There are various solutions to this,
with some divers opting for the more
expensive option of two separate
torches, while others have a blue dichroic filter on a traditional torch so that
blue light can be switched to white as
required. Alternatively a phosphor filter
can be used on a blue light torch to
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convert it to white light.
Contrary to what one intuitively thinks
is the correct white balance setting,
“Fluorescent Light” should not be used
and Auto should be selected instead.
Because the overall levels of illumination
are not high with fluoro-photography, it
is best to increase the camera’s ISO setting to make its sensor more sensitive to
the available light and smaller apertures
are preferred.
Interestingly, as any reflected blue
light is absorbed by the yellow camera filter, fluoro-photography is not as
susceptible to backscatter as white
light photography. Therefore, blue light
Fluorescent coral without blue filter
esting and exciting new aspect of the
underwater world, which will continue
to attract interest because of its uniqueness. Our eyes and senses are attuned
to seeing things as they are illuminated
and reflect light back to us, but with
fluorescence
the light is being
emitted from
the object itself
and all else is
blackness—a
truly strange
and enthralling
experience! ■
Fluorescent coral with blue filter
2004, he worked as a patent examiner
in the field of “computer-implemented
inventions“ at the European Patent
Office in The Hague, Netherlands.
Inspired by Sir Arthur C. Clarke’s book,
Dolphin Island, in autumn of 2010 the
Beyer began building his own fluorescence torches, because he could not
find any commercially available UV dive
lights.
In order to get as close to the experience described in the book as possible,
Beyer initially exclusively used UV LEDs
and built torches of increasing power,
first with a single LED of about 395-410
nm and 1 Watt, then a torch with two
LEDs with 365 nm and about 6 Watt,
and finally one with 4 quadruple LEDs
(equivalent to 16 single LEDs) at 365nm
and 46 Watt.
Together with the dive instructor and
physicist, Lynn Miner, Beyer founded
www.FireDiveGear.com in May 2012, in
order to develop high quality yet affordable equipment for fluorescence diving
and fluoro-photography.
Dichroic or interference filters of different shapes and sizes
strobes do not need to be positioned
as far away from the optical axis of the
camera as they are in white light photography.
Let there be (blue) light!
Night time fluorescence diving and
fluoro-photography is indeed an inter91
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Steffen Beyer has
been a keen scuba
diver since 1988.
He graduated from
Aachen University in
Germany where he
studied computer science and biology. In
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The author’s torch with 18 blue Cree LEDs
and a dichroic blue filter
The author’s current camera set-up
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photo &
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Edited by
Don Silcock
Product shots
courtesy of the
manufacturers
Nauticam S120
Housing
Sea & Sea EOS 70D Housing
Sea & Sea has released their new
housing for the Canon EOS 70D.
The MDX-70D housing is made from
aluminium and features the company’s
new internal optical YS converter, which
converts the camera’s TTL electronic
signal into a fiber output. The housing
features a quick control multi-function
button, leak sensor and an externally
accessible port lock. ■
Nauticam has announced the
release of their new housing
for the very popular
Canon PowerShot S120
compact camera.
The NA-S120 housing
features access to
the camera’s front
command dial, a 67mm
thread on its lens port to
allow the attachment
of accessory lenses and
fiber optic bulkheads for
strobe triggering. ■
Nauticam OM-D E-M1 Housing
The march of the mirrorless cameras continues, and following Sony’s
recent announcement of the first full-frame versions comes the new
Olympus OM-D E-M1 camera. Olympus has built on the tremendous
success of the first OM-D, the E-M5, a camera that impressed
virtually everybody that used it with its excellent functionality and
images. But the E-M5 was aimed at the “enthusiast” market—keen
photographers who were looking for most of what a DSLR offers,
but in a small package. This time Olympus is looking for the E-M1
to tempt the high-end enthusiasts and professionals looking for
that smaller package, and so far the signs are very positive they
will achieve that. Nauticam has responded to the new Olympus
in the usual record time and has announced the release of the
new NA-EM1 housing. The housing is designed to make the most
of the E-M1’s capabilities and looks more like a fully-fledged DSLR
housing with its
attached set of
handles. ■
Nauticam Blackmagic Pocket
Cinema Camera Housing
m
Ca
X-RAY MAG : 58 : 2014
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from
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mic and easy
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Fon: +49 7841 668437
nless and UV
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Nauticam has released their new housing for
the Blackmagic Pocket Cinema camera.
The very highly regarded Pocket Cinema
camera cab record 1920x1080 30P video
in the high quality lossless CinemaDNG
RAW and editing friendly Apple
ProRes(TM) formats. It is also capable
of an incredible 13 stops of dynamic
range. The Nauticam NA-BMPCC housing provides access to the main camera
controls such as record, focus, and lens
control—all of which are placed within
finger reach from the grips. Nauticam has
also angled the housing’s handles forward
by 15 degrees for comfortable use in a
level, swimming position. ■
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oxes
era-b
m
o
www.bskinetics.c
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Ikelite D610 Housing
Sea & Sea RX100
Housing
Sea & Sea has released their new housing for the very highly regarded Sony
RX100 compact camera. The MDX-RX100
is made from aluminium and can
accommodate versions 1 or 2 of
the Sony camera using a bumper
pad kit that is supplied with the
housing. The housing also features a flash deactivation lever,
a multi pad controller and a
control ring for the camera’s
front command dial. ■
Ikelite has announced that it has updated its housing for
the Nikon D600 to accommodate the revised D610 model.
Although externally identical to the D600 housing, the new
D610 has updated circuitry to enable the use of Live View
underwater. The D610 housing has 200-foot depth rating and
is very competitively priced at US$1,600. ■
Gates Sony Z100 housing
Gates Underwater Products has announced their new housing for the
Sony Z100 4K professional camera. The new housing features complete
access to all the Z100’s controls, including manual focus, iris and white
balance. The buoyancy and trim of the housing can be adjusted via the
use of trim weights, and the housing can be outfitted with an HD-SDI surface feed. ■
Fantasea G16
Housing
Fantasea has released their new FG16
housing for the Canon Powershot G16
compact camera. Unlike the Canon
housing for the G16, Fantasea’s
approach is to provide full access to all
camera controls underwater, plus the
housing is also supplied with a double
fiber optic port and a moisture detector as standard. The FG16 is priced at
US$499.95 and in some regions of the
world, Fantasea is offering housing and
camera bundles. ■
Nauticam G16 Housing
Nauticam has released their housing for the Canon PowerShot
G16 compact camera. The NA-G16 housing offers access
to both front and rear control dials on the camera, a 67mm
thread on its port for wet lens mounting plus fiber optic bulkheads for strobe triggering. The housing also features a single
16mm threaded port for attaching an accessory vacuum system
or electronic strobe triggering bulkhead. ■
Aditech MVHS-FS700
Camcorder Housing
Aditech has announced their new housing for the Sony NEXF700 and FS100 camcorders. The Mangrove MVHS-FS700
housing is made from marine grade aluminum, which
has been machined and anodized, while the rear cover
is machined from solid Delrin. The housing features a control system that uses the camera’s LANC control and all
the controls are accessed via 12 external push buttons,
which provides good user feedback via the camera’s touch
screen. Review and framing are achieved via a 3.5 inch
(9cm) TFT rear mounted monitor. The Mangrove MVHS-FS700
housing is available now at a retail price of EU€3,119. ■
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