In article <1998040503311400.WAA10056@ladder01.news.aol.com>, ddavis2419@aol.com says...

>I have a chance to buy a used Nikon Bellow extention. Can anyone tell how to
>operate one...exposure, etc.....I will be using a Nikon FE and Nikon N90S.

These are of limited usefulness, except for high-magnification macro
work, unless used with a short-mount lens (that permits infinity
focus when on the bellows). The bellows minimum extension is considerable,
and most wide-angle lenses will not work on it (unless reversed, where
their magnification will be extreme), normals faster than about f1.8 will
generally not be sharp on it, and some teles will also not be sharp on it.
I would try automatic extension tubes first... (The exception is the
Nikon PB-4 - it is worthwhile to fit on it a short-mount or enlarging
lens of about 105mm to 150mm, since this bellows offers tilt and shift capability.) If you do try one, just set the camera in "M" or "A" mode
and shoot...
David Ruether
http://www.fcinet.com/ruether