In article <900@blake.win.net>, swedenborg@blake.win.net says...
>Comments on quality of the ulrawide zooms by Bob are well taken and
>most appreciated. I assume he was thinking of quality lenses
>like the Sigma. But, I wonder if it would not be nice to have the
>Samyang 18-28 (also apparently more widely marketed as the Vivitar
>17-28 f 4.0-4.5 which costs $139.95 at B&H) with which to take moody
>pix of indoor cafes etc.? The lack of quality might add to the
>charm. This lens only costs $139.95 and for those of us who aren't
>ready to invest in a series of fixed focal length very wide angle
>lenses might be fun to play around with. (rest deleted)

By golly! I think you have hit upon a use for marginally useful
lenses! But, actually, the Vivitar 17-28mm you mentioned did
provide a good learning experience: I, who am a super-wide
nut, and who owns or has owned a lot of fisheyes plus
15mm, 18mm, 20mm, 24mm, 28mm, and 35mm lenses, and who
was a firm believer in the "personality" of each and every
different w/a focal-length, was taught by the 17-28mm Vivitar,
in the very brief period it was in my possession (Thank you, oh
thank you B&H Photo for taking it back!), that there is (surprisingly!)
very little to be gained by bothering to operate the zoom ring on a super wide angle zoom! Not enough range (less than 2:1 on most) to
be interesting, and the modest perspective change possible wasn't
worth the compromises. (I sold my 18mm and 24mm as a result of
that lesson.) My opinion about that zoom: while the optical
quality is far from fine, and unacceptable to me, it is
not so bad that I wouldn't recommend it to someone
who is short of funds and wants to try
some very w/a focal-lengths
Hope this helps.