In article <501dip$nun@sjx-ixn3.ix.netcom.com>, rzuch@ix.netcom.co says...
>In <32238C17.34CB@aol.com> Duane Galensky writes:

>>i wouldn't recommend purchasing either until you've had a chance
>>to look through them to see how they render the scene. they
>>are too expensive to purchase sight unseen. further, the price
>>difference between an 18 and a 20 is huge, and 20 might be
>>more than wide enough!
>>duane

>Ah, if only that were possible. Tallahassee, FL is rather lightweight
>in the photography store selections. I guess I could order them from
>B&H and just return the one that I don't like. Actually, I'm strongly
>considering getting both the 20mm and the 16mm, but I'm going to give
>it somemore thought first.

Good move, and good move. ;-)
Page 22 of the September issue of, yes, Pop Photo (!) has comparison
photos of people taken with a 17mm rectangular lens and a 17mm fisheye.
Though the off-center straight lines are strongly curved in the fisheye
view, the people are much more "kindly" rendered in the (wider!)
fisheye view. The article is about a 17-28mm Pentax fisheye zoom - wish
Nikon made one! (I often use the Nikkor 16mm fisheye on a 1.4X converter.)
Hope This Helps