fstop time multiplier analysis simplification

Hello:

There's a term for making things more complicated than they are, and I don't
remember what it is, so I'll get to the point (irony?).

exposure time multiplier = [(higher f-stop number)/(lower f-stop number)]^2

Don't need the logarithmic factors - I think I had them on both sides of my
equation before so they weren't necessary.

example f 5.6 and f 1.4 are 4 stops apart, so exposure time is doubled 4
times when going from 1.4 to 5.6, or multiplied by 2^(#stops).

Also, (5.6/1.4)^2 gives same result,
and works fine for large f-stops (512/16)^2 = 1024 = 2^10, or double 10 x.

Ignoring other problems with exposure, no need to round off your odd f-stop
number corresponding to the size and distance of your pinhole.

I used f 16 because it gives me relatively long exposure result from light
meter to multiply.

Murray
Received on Tue Aug 7 23:21:51 2001