|
Underwater cameras
by
Peter Rowlands
Reproduced
from in focus 21
(April 1987)
Compared
to land photography, there is a much smaller choice of cameras
for underwater use. They fall into three broad categories
- amphibious cameras for use down to 10 metres, amphibious
cameras for deeper use down to 50 metres and housed land cameras.
AMPHIBIOUS
CAMERAS FOR USE DOWN TO 10 METRES
Recent
years have seen a frenzy of activity in this area. Five vears
ago there was really only the Weathermatic, a 110 format camera,
but now there are 35 mm shallow water cameras available from
Canon (AS6), Nikon (L35AV), and Fuji (RDK). Now Vivitar and
most recently Ricoh have also produced such campras, In simple
tprms, all of these cameras are intended for use in the 'splash
zone' and occasionally underwater. From serious underwater
photographers point of view they are not versatile enough
in that their depth rating is limited and the accessories
.available are either very limited or non existant.
Most
have built-in flash units which would really should only be
used on land as they are to close to the lens that they would
cause extreme backscatter even in clear waters. As they are
aimed at the 'Point and shoot,' user, these cameras tend to
be fully automatic with a limited range of shutter speeds.
They
are however, great fun to use as they allow shots to be taken
in what was traditionally a forbidden area. Surfing, waterfalls,
skiing and even in the shower/bath are just some of the new
locations where these cameras thrive.
AMPHIBIOUS
CAMERAS FOR USE DOWN TO 50 METRES
Althouh
the choice is extremely limited, this type of camera is the
most widely used underwater. For serious underwater photography
the most popular is the. Nikonos which is fully waterproof
down to 50 metres.
For
those who flinch at the latest prices, there is the Sea &
Sea Motormarine 35 which has a range of accessories including
close-up and wide-angle lenses and external flas.hguns. This
is the motor-wind and rewind camera with a 35 min fixed lens.
A built-in light meter indicates correct exposure settings.
Because
it has been produced in various models since the late 1950's.
the most popular amphibious camera is the Nikonos which has
interchangeable lenses, a wide range of accessories and, with
the latest version, sophisticated exposure control for both
available and electronic flash. Their availability throughout
the world has established them as a standard and independent
manufacturers have added to Nikon's accessories to make the
Nikonos system by far and away the most comprehensive.
Nothing
is perfect, and amphibious cameras do have some drawbacks.
The main one being that they do not allow 'reflex' viewing
through the lens. This means all focusing has to be done by
estimating the camera to subject distance and setting the
lens accordingly. Such a limitation is not too terminal as
most underwater photographs tend to be taken with close-up
lenses which incorporate a framing/focus device or with wideangles
which have a greater depth of field, so reducing the need
for ultra-accurate distance estimation.
The
big advantage of amphibicus cameras is that they are small
and easy to use. You load them just like a land camera and
there are no external controls to line-up when assembling
the camera, Their accessorv lenses are corrected for underwater
use and so tend to give higher quality.
That
there are so mariv Nikonos in use today is indication enough
of heir
suitability for serious underwater photography. Like all equipment
they are not perfect but I'm sure that if we had an SLR Nikonos,
we'd find some fault with it!
CAMERA
HOUSINGS
The
alternative to an amphibious camera is to put your existing
land camera into an underwater housing. These housings fall
into two sections. Flexible for use down to 10 metres and
rigid housings for use down to 100 metres.
The
flexible housings have similar attributes to shallow water
cameras in that they are not intended for serious use but
rather are ideal for using existing, equipment in conditions
which would ruin normal cameras. They can accomodate a wide
range of cameras and there are different sizes to allow flashguns,
motor drives and zoom
to be used. Being flexible, they are far from easy to use
but do allow land cameras to go underwater at a comparatively
small cost.
For
more dedicated use, there are rigid housings available for
most 35 mm SLR and some large format cameras. The big advantage
of using a land camera in a housing is being able to see what
is in focus and to be able to compose accurately. In addition,
you have a much wider choice of lenses and other accessories
available. Being able to see whether your subject is in focus
allows you to use macro lenses which are very versatile, These
are ideal lenses for nearly all forms of srnall marine life. |
