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Re: Photography

Just a short note to augment Karen Randall's excellent treatise from
this weekend.  

All the photos on my website were taken using only the tank lighting
(4 x 40 watt bulbs (1.6 watts/gallon) or 2 x 175w metal halide bulbs
(3.5 watts/gallon)).  

If you note the "watts/gallon", you'll think that the MH setup would
be *much* brighter. However, one F-stop or shutter speed step is
double the light intensity and the MH bulbs are suspended futher from
the water than the FL bulbs. The exposures are about the same from
either setup.  If I lower the MH hood right down to the water, I can
maybe go from 1/30 to 1/60 of a second.

I've tried a singlem, decent flash in the front (held off at an angle)
but it produced poor color and lifeless photos.

Oh, yeah, one photo was taken with sunlight beamed in from the outside
with mirrors. Nice effect but difficult to do. I was able to only get
a small spot of light after beaming off two fairly good size mirrors. 

I've used a variety of films, slide and print, 100 ASA to 400 ASA.
Try different kinds to see what works best with your lighting setup. I
don't pay extra for "professional" film; it seems that it is merely
fresher film and it is usually stored under better conditions but I
have seen no qualitative difference. I think the lack of professional
equipment and a studio set up negate any improvement better film would
make.

My camera is an older Pentax ME with a 50mm F2.0 lens and a 30-70mm
F3.5 zoom lens. The 50 mm lens gives me more favorable exposures
(numerically larger F-stop for better depth-of-field with the same
light level) but the zoom lens give me better composition control.
Most exposures are 1/30 of a second.  I've gotten a few nice photos
at 1/15 (mostly plant closeups and discus). 

Be sure to "bracket" your shots if you have exposure control.  Take
three photos of each scene, normal exposure and 1 F-stop over- and
under-exposed. Over-exposing seems to work better for slides than the
normal exposure.  Perhaps the peculiar lighting conditions in a tank
confuse the light meter (or I have a crummy light meter :-). 

Definitely expect to take many, many photos to get one good one.  I
went through 18 rolls of 36 exposure film to create a plant seminar
slide show with 40 aquarium slides. Luckily, there were also 40 "text"
and "drawing" slides so I didn't need to go through 36 rolls to fill a
carosel <g>.

George Booth
Need info? http://www.frii.com/~booth/AquaticConcepts.htm