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Re: ADA Contest

>From: "Madan Subramanian" <madans at satyam_net.in>
>Subject: Re: ADA Contest
>It doesn't take much to photograph your aquarium if you use 50 ASA film.
>I got a friend a professional photographer who had never used an aquarium as
>a subject to photograph my aquarium for the ADA contest but he used 100 ASA
>film and ended up needing more light.
>My tank is 3' x 2' x 2' and he couldn't get the depth of field required for
>so deep a tank using 100 ASA film and a f stop of 22 and a half ( what ever
>that means).


         50 ASA is slower than 100 ASA film. So therefore needs MORE light. 
could have used 200 or 400 ASA which requires lesser light but will produce
grainier pictures. Slower film produces sharper pictures.

         The depth of field required for a glass aquarium will be less than
normal photography due to air-glass-water layers light path. This 
diffraction (?)
causes the loss of visual depth in glass tanks. You could have good crisp 
focus with even F11, which mean a lot less light is required.

Raj, vu2zap
Bangalore, South India.