At 10:10 AM 4/26/01 -0400, you wrote:
>What you've discovered is the inverse square law. When you do bellows or
>extension tube work, your exposure has to increase when you extend your
>bellows or use of tubes. This is not in a linear fashion but increases
>proportionately with the distance. If (and this is the important if) your
>flash is attached to the front standard of the bellows or the filter ring of
>your lens, whenever you extend your bellows the amount of light the flash
>puts on the subject will increase also. But again it will not increase in a
>linear amount depending on the extension but in proportion to the square of
>the distance.
>
>Both of these cancel out, as you have found out through experimentation.
>Congratulations for empirically finding this out.
Actually, I've had enough physics that I knew about that. You're giving me
a little too much credit.
Although I mentioned the flash, which was attached to the top of the camera
with an extension that allows me to angle the flash downward, I still get
the same exposures when using available light.
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