At 10:13 8.2.2001 -0500, you wrote:
>Your understanding of the working distance is correct. The thing is that
>the FREE macros change their focal length but they also change the
>positions of their nodal points, so that the working distance at 1:1 of the
>FREE lens is longer than the working distance of a 60 mm lens put on tubes.
>So, the final effect is like this: the focal length becomes smaller and the
>lens-to-subject distance does too, but not quite so fast. So the effect is
>like using a lens with a focal length of 60 mm but with lens-to-subject
>distance of something like an 80 mm lens.
>
>Note that the same happens with the 200/4 Macro.
>
>Cheers,
>Boz
Boz, thanks for a great explanation! Might look at the "new" "fangled" IF
macro lenses after all :)
regards,
Frantisek
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