In article <19970312201200.PAA15014@ladder01.news.aol.com>, iggycpa@aol.com says...

>when using a 77-62 stepdown ring on a 80-200 nikon zoom, will there be a
>problem at f2.8,f3.5etc? i am planning to use this setup for macro work.

Before you added the last part, my answer would have been that there
probably would have been a problem with vignetting, especially at
smaller stops (but maybe at only some FL's...), but with macro (using
achromats in preference to ordinary close-up lenses...), you can often
use a considerably smaller glass diameter without problems (though using
wide apertures for macro work may not be wise if you are looking for
good sharpness from this lens, and also reasonable DOF...).
Hope This Helps