f2.8 24/70 or 28/80 Autofocus Zoom for istD

I'm looking around for a f2.8 "medium" zoom for my istD.

It looks like the choice is Sigma, Tokina or Tamron - can anyone offer any guidance regarding quality/handling/value ect?

Any help much appreciated.

Thanks.

Andy

There have been many comments made on the dpreview forums regarding issues with sigma lenses and the *istD. There is apparently a problem with backfocus, made worse by sigma not stumping up for the protocols for the KAF series of mounts - they reverse engineered, and it looks like they might have made mistakes. If you go to dpreview and check posts by Wallyoz you will find quite a few quite strongly worded comments. Just bear in mind that Wally can be a little forthright, and occasionally overstates his case. Still, he rasies some interesting points.

the forum may be found at http://forums.dpreview.com/forums/forum.asp?forum=1036

I have the Sigma 28-70 f/2.8 DG, used only on film bodies (MZ-3 and pZ1-p), it's a good lens, but there is distrortion noticable at wide-angle. Sharpness is good, however.

Hope this helps

Matt

Well, I'd go with Mattie's comment too.
Having tried a few different lenses (including a Tokina 28-70/f2.8 which was rather nice, but a little cool, IMHO), I have stuck with the SMC-FA 24-90/f3.5-4.5.

I have learned my lesson - that f-stop is not everything Compatibility and distortion are important, of course, but also: flare control, bokeh, contrast, and colour. To my eye, the Pentax has it in bucket loads. It's not the absolutely sharpest lens, but you'd have to work hard to get me to trade it for anything else Since the *ist-D has auto compensation for ISO, I've not had any real problems with lens speed, even doing theatre style work and getting results that I couldn't believe I took

Range-wise, the 24-90 is great for the *ist-D. It stays on the body nearly all the time.

That said, there are other lenses out there... just depends what your tastes are! (Oh, and www.mxv.co.uk currently have the 24-90, as well as a Tamron 28-70 f2.8 )

Hope that helps,
Matt

I agree, the Pentax 24-90mm is a superb lens. A bit of barrel distortion at the wide end, so not ideal for architecture (in common with a lot of modern zooms) but overall excellent.

Hi,
The MXV price for the 24-90 seems a little high. You can get a new one for £299. If you don't desperately need the extra stop, the Pentax 28-70 F4 AL is a cracking lens for a ridiculous price. You might also want to consider the Pentax 28-70/2.8FA. It's new price is silly but I managed to get a near mint secondhand one for about the same price as a new Sigma EX.

Kim

Andy, you name looks very familiar, where have i heard of you before?

I have both the 24-90 and the 28-105 power zoom. I concur with what's been said about the former: mechanically it's pretty sloppy, but the pictures are very sharp, and the range suits the DSLRs. As for the latter, I haven't had it long enough to have formed any conclusions yet, but it is quite well regarded.

Why both? Let's just say that I got the 28-105 at a very reasonable price (unlike the other one!). The only other zoom that appeals strongly in terms of range is the 18-55, but I reckon the image quality of the 24-90 is better (notwithstanding my earlier comments). Also, I believe (but haven't checked) that it is not compatible with 35mm cameras, so will be no good if a full-frame DSLR ever emerges.

The 28-70 f4 is universally said to be very good indeed, but the lens has a fatal flaw: it suffers from element separation, and there is no (economical) cure. If you buy one, don't pay too much for it.

George

Thanks for all your comments - much appreciated

What I'm actually looking to do is minimise depth of field. I would look to use a f2.8 lens mostly at f4 for this purpose.

I have a 28-105 Power Zoom - which is the lens I use most, whichever body I am using, but I tend to use this mostly at f8 or f11.

I also have an SMC Pentax M f4 75-150 and a Takumar f2.5 135 - so obviously these will do the job - it's just that autofocus zoom is so much more convenient.

Thanks again for your help.

For John Riley - you know me through north-west monochrome.

Andy