Originally posted by Rondec I owned the earlier 30mm f1.4 and was extremely disappointed by the borders, even stopped down. Contrast on it and the Sigma 70-300 I owned were really not great.
The 30mm f/1.4 Art is allegedly much improved over the version you owned (I can't opine since I've never owned the older model). Sarah at Lensrentals said the following:
"The Sigma 30mm f/1.4 DC HSM A1 is a definite upgrade from the previous version. Right out of the case you can tell the build quality is much stronger, with a solid, accurate focus ring. Optically, the image quality is similar in the center to the previous version, but the corners are much sharper and focusing is more accurate making it worth the price difference."
... while Roger Cicala said:
"Like a lot of people, I was hoping for a crop-sensor version of the Sigma 35mm f/1.4 full-frame lens; an amazingly high-resolution optic. This lens isn’t that good optically. It’s a very nice lens with good resolution and excellent corner performance. If corner performance is important to you this lens is a significant upgrade. If you are more interested in center resolution, than optically it’s not better than the original.
However, I’d still consider this a worthwhile upgrade for a number of reasons. Build quality is far better. The new lens can be accurately focused manually, something that live-view shooters like myself found was difficult to do with the original."
Originally posted by Rondec The 18-300 is probably fine for what it is, but somehow Pentaxians don't seem enchanted by super zooms. The 17-50 is probably fine, but truthfully, the lens that Pentaxians always seemed to migrate to if they wanted an APS-C walk around other than Pentax's own 16-50, 17-70, 18-135, or 16-85 was the Tamron 17-50 f2.8, which for whatever reason always seemed to get better reviews than Sigma's.
I'm not a big fan of superzooms either, but there are occasions where I think they can be useful... invaluable, even, so long as the limitations are understood and accepted. I actually bought my Sigma 18-300 long after I sold my DA18-270, and some time after I'd become well equipped with very good primes, the 17-50 f/2.8 HSM and HD DA55-300. It doesn't get a great deal of use... but when needed, it's very handy. Yes, it has many compromises, but as superzooms go, it's good. Centre performance is actually pretty awesome for the type of lens, and whilst the borders and corners fall well behind, it's more than usable in most situations.
The 17-50 f/2.8 HSM, though, is better than just "fine" - it's really
very good indeed, at least in my opinion. It easily bests the DA*16-50, and is more-or-less comparable to the Tamron 17-50 f/2.8, with a mix of those who prefer one or the other. The Sigma has a much flatter field, and the HSM is nice, since it's virtually silent. I understand the build quality of the Sigma is slightly better, which I can believe given that I own the Tamron 28-75 f/2.8 and, whilst it's one of my all-time favourite lenses, build quality doesn't quite match the Sigma.
Incidentally, contrast on all three of the lenses I mentioned is excellent. As for colours... I like them. I've heard one or two less-than-stellar opinions, but only a very few, and I can't for the life of me think why. Personal preferences, I guess.
I'm not trying to fly the flag for Sigma, here... Just offering another, different view for balance.
Originally posted by Rondec My point is mostly that most of the more recent (and better) Sigmas never made it to K mount and so we are judging sales of Sigma's lenses for Pentax based on older and less well regard lenses. I guarantee there would be folks who would purchase lenses like the 150-600 or their Art lenses over Pentax's current offerings, particularly if Sigma figured out how to make them focus a bit better on Pentax cameras.
Yes, absolutely. Actually, the 150-600 in particular would - I'm sure - have a solid market in K-mount if AF was reliable. I have the Tamron 150-600 (first generation) in Sony A-mount and it's a wonderful lens. The Sigma offerings are supposed to be better still.
Interestingly, I've read that AF problems on some of the Sigma lenses aren't unique to the K-mount variants. Apparently, a lot of folks shooting Canon weren't happy with AF on the 35mm f/1.4 Art and the 18-35 f/1.8 - improved somewhat by firmware upgrade, but not fully resolved...
Last edited by BigMackCam; 09-08-2019 at 02:39 PM.