>d_ruether@hotmail.com (Neuman-Ruether) writes:

>> I tried a Tokina ATX 17mm, and was disappointed - edge/corner
>> sharpness never got good at any stop. For non-critical users,
>> I guess it would be OK...

> I'm looking at the corner of a Colorplan-projected slide.
> The image is meter wide and I'm 25 cm away. The corner
> sharpness looks good. Can you define what you mean by
> terms 'good' and 'non-critical'?

(Keeping in mind that samples vary....)
The 17mm ATX Tokina I tried was soft (as in "not sharp"...)
at wide stops at the edges/corners - which I consider acceptable
in a super-wide, if performance improves considerably and the
lens is capable of acceptable sharpness at the edges/corners
(as in, "looks sharp enough, though it may not be quite so sharp
as the center") when stopped well down. The Tokina failed
to do this. BTW, I shot the same material at the same time
on the same roll of film with a Nikkor 20mm f2.8. The difference
was like the proverbial "night and day" - one lens produced
nearly uniformly sharp images center to corner by f5.6-8,
the other didn't at any stop. (I check film directly with
a good 10X magnifier - projection/reproduction/etc. can
often cover a variety of ills [but, as I said, "For
non-critical users, I guess it would be OK..." ;-].)
Perhaps you have a better sample than I had...