> I have also had Tokina and Tamron AF lenses, and in my view they have > been more reliable than the Sigmas I've owned or borrowed.
This has been my experience, too. However, to be honest, I have not had much experience with Sigma lenses - none with any autofocus lenses ever, and none with any manual focus lenses in many a year, so this should not be taken as a criticism of any current Sigma lenses, per se. You see, between the sloppy build quality I had found in a couple of Sigmas some time back, and the frequent reports of mechanical problems I had heard/read since, I developed a "why buy a Sigma when there are so many good Pentax, Tokina AT-X, Vivitar VS1 (at one time, up until the mid-80's, say) and Tamron SP lenses to buy instead?" philosophy. (My experiences with quite a few manual focus 3rd-party lenses of the above lines has been mostly very positive, although I have used only a couple of Tamrons.) On the other hand, I have heard/read some good reports on the Sigma 70-200/2.8 here, so it does sound (intellectually) interesting. The only "problem" is that I don't really need another 70/80-200/210 lens )<g>), so I am unlikely to end up trying it. [I was lucky enough to pick up an FA* 80-200/2.8 at a good price a while back, and since then both my manual focus and autofocus Tokina AT-X 80-200/2.8's have been gathering dust (figuratively - they're stored in cases - <g>); the manual focus version is quite good, but I never ended up using the autofocus version too much, so I can't say much about it yet.] My only "complaint" on the FA* 80-200/2.8 is its two-touch design - I personally prefer (and YMMV) one-touch zooms, but I do see how that might be difficult to pull off in an autofocus lens. Also, a point I've made before here on the PDML is that there ~is~ a difference between the zoom range of 70-210 (common in the slower zooms) and 80-200 (common in the faster ones, although the Sigma does claim to be a 70-200 lens). I do wish the fast 80-200's were 70-210 lenses - a zoom ratio of 3:1 is definitely nicer than 2.5:1 (and is sometimes significant). [Of course, lens tests almost always show that lens makers "fudge" on their FL specs - telephoto primes are almost always a bit shorter than what is claimed, wide angles are almost always narrower than what is advertised, and zooms tend to have narrower zoom ranges than the specs suggest - but I digress...] I suspect that it must be a lot harder to make an f/2.8 70-210 than an f/2.8 80-200 and still amintain high optical qualities. I've been toying with a 70/80-200/210 lens comparison shootout (I've got so many of these lenses, both fast and slow, kicking around here). However, this is awaiting the hopefully positive results of all of my pre-Birthday (September) *ist-DS hinting - I can't justify or afford the expense or the scanning time of doing any film-based "shootouts" anymore. [It's kinda funny, but, once I have a DSLR, it will probably pay for itself quickly with the sale of "liberated" lenses, i.e., lenses that just haven't been gotten rid of yet because I don't really know yet which ones are worth keeping or not - <g>.] Oops - sorry about the long post... Fred (the packrat)
