Timothy
Parker Consulting Incorporated
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Underwater photography Startling scenes abound underwater, whether you’re scuba
diving or snorkeling. Capturing these colorful, almost alien scenes with your
digital camera is well within your capabilities once you understand how to use
your digital camera underwater, and the differences between underwater and
terrestrial photography. Underwater photography used to be limited to
professionals with expensive, watertight equipment and tons of support gear, but
the development of inexpensive housings allows you to take many digital cameras
beneath the waves and capture the world that exists there. Let’s step back a few years. Prior to digital cameras, underwater photographers used
dedicated film cameras designed to withstand the pressure of working at depths,
as well as protecting the sensitive film and camera workings from water damage.
The most popular underwater film cameras are the Nikonos line from Nikon,
used by the majority of underwater professional photographers.
The Nikonos V camera uses standard 35mm film, has automatic exposure
calculations, but requires the diver to adjust focus and f-stop manually on the
lens. The Nikonos RS, a very
expensive SLR, added automatic focus and lens control to the family. Nikon isn’t the only underwater 35mm camera available.
Sea and Sea and several other companies offer waterproof cameras designed
for film photography, but the Nikons dominates the professional world. Alternatives to dedicated underwater cameras were developed
with advances in plastic and composite bodies.
Several companies offer housings for terrestrial SLR models such as the
Nikon and Canon families. Digital
camera housings enclose your land camera in a clear polycarbonate housing that
uses O-rings to seal all access areas from water seepage. Knobs and levers on
the outside of the housing connect to the camera controls directly, allowing you
access the features of your camera. Depending
on the housing used, you may not have all the features of your camera available
underwater, but all the basics are usually provided.
Housings tend to be expensive ($2000 or so for a top-of-the-line model)
and bulky compared to Nikonos cameras. Still,
they offer the ability to use an existing camera with advanced electronics
underwater. Simply diving with a waterproofed camera wasn’t enough
for film work. Colors in the water
start to disappear as soon as you submerge.
At 20 feet underwater, colors are almost entirely lost, and film cameras
render the whole scene in shades of blue, usually vastly underexposed even with
fast film. Flash units are a necessity below five or six feet, except on very
sunny days. Underwater flash units
provide natural illumination for a scene and bring out the true colors, but for
adequate lighting a lot of flash power is required. Underwater flash tends to quickly lose intensity because of
the density of water, so high power units are required for anything but
close-ups. A typical underwater
flash setup with have two or more lights, with 400W flash units or more used. The advent of digital photography changed underwater
shooting. For one thing, film speed
effects and color correction could be performed in software, reducing the light
intensity needed for flash shots. Also,
digital cameras tend to be smaller than film cameras, requiring less housing.
Although there is no underwater SLR digital camera currently available, a
couple are under development but will be expensive and aimed at the professional
market. Lenses underwater Don’t assume that the field of view your camera lens
presents you with above the water translates to the field of view underwater.
Because water is a more dense medium than air, it causes several effects
that you need to compensate for. First, distances are deceiving.
The fish you think is three feet away is really only two feet away.
To gauge distances underwater, many photographers use their arms: extend
your arm to the same distance as the subject (or almost touch it if it doesn’t
move) and that’s about three feet. Some
digital cameras will focus correctly underwater, some won’t.
You may have to resort to manual focusing to capture the subject
properly. Most digital cameras have fixed lenses, so your options may
be limited when it comes to lens choices. Cameras
with replaceable lenses (such as Nikon’s D1) allow much better choice of lens,
but these must be changed out of the water, not under! A lens’ field of view is altered underwater, too.
A 35mm lens on the surface will not behave the same underwater.
You should experiment to find the effect your camera’s lens has on your
exposures. A good way to do this is
to photograph a fixed object such as a wreck or coral field at different
distances, with different settings on your lens if it is a zoom adjustable, and
measure the field of view from the results.
Because many digital camera lenses are not quite as rated (for example, a
“35mm” lens on one camera actually tested as a 46mm lens), testing your
camera is a good idea even if you don’t have a zoom. Underwater affects the distance you can focus to, too.
For example, many short lenses (such as 15mm through 35mm) cannot focus
closely enough to capture small animals and fish on a reef.
On the other hand, these lenses have such a wide field of view that
photographing objects ten or more feet away results in a subject too small to
see on the final print. Short
lenses are designed to capture reef panoramas, other divers, or schools of fish
at reasonably close distances. Medium
length lenses (35mm to 50mm) are good for shots of individual fish and animals,
although not for close-ups or wide panoramas.
Longer length lenses (over 50mm) tend to be of limited use underwater
because light from a flash cannot project far enough to illuminate a distant
subject. The most useful lenses underwater tend to be close-focussing
or macro lenses. Macros allow you
to move in close to static subjects such as coral, anemonae, or slow-moving
animals like starfish and nudibranches. Close-focus lenses allow small fish to
be captured from a distance of less than a foot, although skittish fish require
patience. It is unlikely that you will be able to use the viewfinder
on your camera underwater, and use of the LCD display tends to drain batteries
quickly. If you do a lot of
photography underwater, you will quickly develop a feel for positioning and
distance without having to look at the camera.
This skill is handy not only underwater, but also on land, too!
It lets you get snap shots that you’d miss if you resorted to the
viewfinder or LCD. Digital camera CCDs react differently underwater than film.
The color sensitivities of CCDs are different than film, of course,
meaning that the colors you see underwater may not be the same as those rendered
by your CCD, even with proper flash illumination. Don’t rely on a camera’s
built-in flash: it isn’t powerful enough to light up even close fish or
animals. Instead, invest in a
high-quality underwater strobe, or rent one at a local dive shop.
Strobes attach to most housings through a waterproof connector. Handling underwater cameras Diving with an underwater camera and flash setup is not for
the novice diver. Working with a
camera requires concentration on the camera and subjects, not on the diving
itself. If you’re a scuba diver,
you should have total control of your buoyancy and be familiar with your dive
gear before tackling underwater photography seriously. Most underwater cameras
and flash gear is neutrally buoyant. The techniques involved in photographing underwater take a
while to master. Perhaps the
hardest lesson is to properly frame your subject, taking in account distortion
from water, distance to subject (which is deceptive underwater), camera lens,
and flash coverage. Maintaining
your position to photograph a subject without scaring the target or drifting
away requires patience and practice. Most successful underwater photographers use two flash
units positioned at angles on either side of the camera. This provides natural even illumination, but means you’re
handling about 30 pounds of gear (which is almost weightless underwater)
requiring both hands to operate. Make sure you have someone who can hand you
your cameras when you enter the water, and also take them from you when
surfacing. Moving in and out of the
water with a bulky camera setup is an invitation to damage the equipment or
yourself in the process. Not a diver? Don’t
want to lug 60 pounds of dive equipment and cameras on vacation?
Try snorkeling instead! Some
of the best pictures of underwater life can be captured close to the surface,
easily within snorkeling reach. Reefs
tend to be close to the surface near shore, with fish and coral life abounding.
Underwater housings for cameras can be used without flash near the surface, as
colors will render almost naturally from sunlight alone. Snorkeling is also a
great way to learn to handle your underwater housing and learn the skills
necessary to use your camera when diving. Underwater photography is a rewarding field, adding a new dimension to your photographic skills and producing stunning, colorful images. Housings are expensive and not for the casual user, but renting a unit and trying underwater photography will add spice to your next vacation. Camera housings and diving Housings for cameras range in price and features over a
huge range. So-called “water
resistant” housings are inexpensive but tend to leak when submerged, even at
shallow depths of four to six feet. Unless
you are willing to risk losing your camera to water damage, avoid
water-resistant housings. True underwater housings are usually made of polycarbonate
(clear plastic) or a combination or polycarbonate, plastic, and rustless metal.
Housings are designed for specific cameras, so make sure you select the correct
housing for your model. Housings are usually rated for a maximum depth, beyond
which the housing could leak or crack. Most
underwater housings are rated to 200 feet or more, well beyond the safe limits
for no-decompression diving of 120-140 feet. Expect to pay quite a bit for a good housing.
There are several vendors of housings, and not all support all camera
functions. Typically, housings range from $750 to $2,500 depending on the camera
and features. (The housing usually costs more than the cost of the camera that
is inside, making underwater cameras such as the Nikonos a better value!) If you plan to use your camera underwater on vacation or as
an experiment, consider renting a housing from a local dive shop.
Most dive stores maintain a few rental cameras and housings, and a
week’s rent of a hundred dollars or so is much less expensive than buying a
housing that you’ll use only once. What to look for in a housing:
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