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Underwater Photography Primer
that states that the Ike housing is no good. I have to disagree. I'm sure it's not the slickest housing to use
but it does the job. The shutter release is spot on and the ports are as good as any others I've seen. I'm
quite pleased to have saved money on the housing to spend on extra ports and lenses.
How does the housed camera compare to the trusty Nik V. For macro work it's superb. I am not stuck
with one magnification, selected before getting in the water and I've no framer to scare the fish. For wide
angle it's closer to call but through the lens viewing wins the day in my book. You also have the
capability to use zoom lenses with the housed camera.
-- Ken Byrne, November 22, 2000
I just wanted to give my 2 cents worth about a previous equipment comment (you all have covered the
bigger issues very well!). A previous comment about autofocus systems within a housing just isn't true.
Autofocus works extremely well underwater. Color absorption has nothing to do with the autofocus
system, it focuses based on contrast. I've been doing u/w photography for about 8 years and have had a
housing for my N90s for 3+years. The only time I've had problems with the autofocus was when it was
just too dark (can and does happen on dry land) AND I did not have my spotting light mounted on my
housing. The spotting light is a flashlight which allows you to see your subject in less than ideal lighting
conditions and also provides enough light for autofocus to work. At night I use it as my dive light.
During daylight hours I estimate that I've had to use the spotting light maybe 5% of the time.
Just wanted to clear this up.
-- Ken Aaron, January 14, 2001
A few points that haven't yet been covered, or could use some clarification:
Housed Cameras: Focusing a housed camera is completely different depending on whether you are using
a dome port or a flat port. A flat port reduces the included angle of the lens, but focuses just like a
regular lens. A 35mm lens is more or less equivalent to a 50, etc. Most u/w photographers use a flat port
ONLY for macro work. A dome port, on the other hand, does not affect the included angle of the lens, i.
e. a 20mm lens under a dome port covers the same 94 degrees or whatever that it does on land.
HOWEVER, the lens focuses not on the subject, but on a "virtual image" projected on the dome port.
The virtual image is much closer than the real image, so you are using the close focusing capabilities of
the lens even if the subject is a hundred feet away (not that you are likely to get a picture at that distance
anyway). So, to use a dome port you need a lens with excellent close focusing capabilities, or a screw-in
closeup lens, or an extension tube. Many underwater photographers like the 24mm Nikkor because of its
excellent sharpness at extremely close focus. BTW, depth of field is very high with a dome port, you
hardly ever have to refocus the virtual image. I used to use a 24mm on a Nikon FE inside an old
compact Tussey housing and was quite pleased with the handling and the results.
Strobes and backscatter: Perhaps the biggest problem in using a strobe underwater is backscatter, the
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