Re: PHOTO-3D digest 1391

[P3D Bob Howard <bobh@xxxxxxxxxxxxxxxxxxxx>]

RE:Hayden, the 3D Bear on Tiffen Close up LENSES!!
Fortunately on ANY camera when set at infinity the close up lenses give 
the same infocus distance, so the real focal length does not matter.
The distance focussed upon is the reciprocal of the diopter in meters.
So a #1 + 1 meter or 39 inches. #2 = 1/2 meter or 19 1/2 inches and #4 
is 1/4 meter or 9 3/4 inches. This is what the tables show in the lid of 
the old Kodak ones without regard to lens they are put on. Focusing away 
from infinity does not drastically get you closer..an inch or two. BobH


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