> Date: Thu, 26 Feb 2004 04:53:11 -0500 > From: Lon Williamson <[EMAIL PROTECTED]> > > As I understand it, distortion is _inevitable_ in a lens > as wide as 24mm, which is why, for example, a 35mm is better > for group portraits.
I'm not sure this is true. Certainly retrofocus design does not help, but I understand that both the 20-35 and 17-35 Nikkor zooms have a point in the middle (about 22 for the 17-35 IIRC) where no barrel or pincushion distortion shows. My 20/2.8 Nikkor's don't have much barrel distortion, and the 28/3.5 SMCT supposedly has less than .5% distortion. 24mm has never been a particularly popular focal length, either, and has not been as aggressively developed as the 28mm or 20mm by most manufacturers. > Winston wrote, in part: > > ....I'm not satisfied with the FA 24/2. Too much distortion, > > and sharpness could be better at wide f-stops. It could well be that the "f/2.0" part is more to blame than the "24mm" part. There are additional design considerations to deal with when making glass that fast. I know of very few f/2 or f/1.4 traditional lens designs which perform well wide open, and in most cases at f/2.8 to f/4 they are outperformed by f/2.8 designs from the same manufacturer. 24/2.0 is a very fast ultrawide. Canon makes an f/1.4 version but it is an order of magnitude larger than the f/2.0s, as is Nikon's 28/1.4. Pentax once made a prototype 20/1.4 which I really wish they'd produced. Olympus made a 21/2.0 (?) which I seem to recall reading unfavorable Olympus-user ratings of. Nikon did not make an AF version of their 24/2.0 and shows no signs of making a 20/2.0 which I'd buy in a heartbeat. I suspect that this shows that it is prohibitively difficult to make a good fast ultrawide. Another reason that the 1.5x FOV crop on DSLRs is a BAD idea for pros! DJE
