Macro/hypo question

[erker@xxxxxxxxxxxxxx (Greg Erker)]

Hi,

  I took some slidebar macro stereos the other night using my
SRL and 50 mm lens with lens reverser. One problem I had was
figuring out how far to move the camera between exposures. If
I use the 1 in 30 rule is it 1/30 of the distance from object
to the front of the lens, film plane, or some intermediate point?
It makes a big difference when the front of the lens is 4" from
the object and the film plane is about 7".

  I know that you want 1.3 mm (or whatever the number is) of
on film deviation but I am not enough of an optical guru to
figure out what that means for my setup. If someone could help
me with a formula or table I would appreciate it.

Thanks - Greg



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