NAUI Advanced Scuba Diver
90 Underwater Photography
FIGURE 9-3. Cameras come in many designs from point and shoot disposable to sophisticated amphibious models used by professional photographers.
appear closer than their measured distance. Understanding
and compensating for this phenomenon is important for
photography. The lens on a camera must be focused, and
if you focus it for the actual distance to the subject, your
picture may not be sharp because the apparent distance
to the subject is less than your setting. You must focus on
the apparent distance as perceived by the eye and as would
be seen when focusing through the lens with a single lens
reflex camera.
Refraction also makes it harder to accurately point a
strobe or a flash at a subject. You will learn how to compensate
for this in the Picture-Taking Techniques section
of this chapter.
EQUIPMENT
All types of cameras may be used underwater as
long as they are housed in waterproof, pressure-proof
containers that allow access to the controls. Still cameras,
movie cameras, and video cameras are all used successfully
underwater. Even with the great popularity of digital
video, the majority of underwater photography is “still”
photography, so we will concentrate on that area; but the
principles and techniques of underwater photography for
still cameras apply to cinematography and underwater
video as well.
The two basic types of underwater cameras are
amphibious cameras and housed cameras. Both are capable
of producing quality pictures (figure 9-3). The advantages
and disadvantages of each type are presented in detail
in the NAUI Underwater Digital Imaging course.
The capability to interchange lenses or otherwise
change focal length is a desirable feature found on many
cameras used underwater. Changing lenses is less convenient
because the lenses must be changed above water.
Clip-on supplementary lenses may also be available