Sigma or Tamron 17-50 2.8?

I'm looking for a sharp mid to wide angle zoom to fit in between my DA12-24 and Sigma 50-150. (I'm not that interested in the DA*16-50; too many indifferent IQ comments and SDM issues, and I'm not fussed about its WR properties as I rarely immerse lenses.) I’m looking for a step up in IQ from my DA 16-45.

I'm think about either the Sigma 17-50 EX or the Tamron 17-50 Does anyone have experience of the Sigma, or even better both. The few reviews or comments of the Sigma I’ve seen are good, but there are not that many reviews about. The Tamron gets great reviews, but the one I tried had a very tight zoom ring, which I felt spoiled the feel of it. Have other people had that issue or was it just the one I tried?

Thx

Nick

I have the Tamron and have handled the Sigma, albeit not in the Pentax mount. I don't find the zoom ring on my Tamron too tight at all, but it is a little tighter than my other zooms so it may be a matter of taste. I wouldn't hesitate to recommend the Tamron based on my own experience, and I do not personally feel that the Sigma is worth the extra cost. YMMV.

Tamron

Pros: Smaller, lighter, cheaper, and according to certain reviews/opinions, sharper.

Cons: Noisy AF, Rumored BF/FF problems in some copies (I personally have not had any problems), acceptable build quality - but only just (meaning if it was even just a little bit flimsier, it would worry me. As it is I can cope).


Sigma

Pros: Quiet AF, much better build quality.

Cons: Larger, heavier, more expensive, possibly not quite as sharp.

Tamron, non-VC BF/FF you can sort out with AF adjustments in your K-5. Two of my four lenses are having ff/bf problems and they are not Tamrons....

I have the Tamron on the Nikon mount, excellent lens. Yes it does not feel as well built as the Nikon equivalent heck it does not feel as well built as the 18-55 Pentax one but it is really sharp and nice lens. On the D40 it was slightly slow to AF as well, with a D7000 it was much better. So maybe with the K-5 though noisy it will be fast enough.

Mark got the P/C on the spot I think.

BTW no tightness on mine.

Whilst the Tamron is good the build quality leaves a lot to be desired, one of my friends has the new Sigma 17-50mm with built in OS & it feels very well made, he is happy with the images from it, but then the price is in the same ball park as the Pentax....

I have had no need to upgrade my Tamron, however I don't expect it to last longer than 5 years either...

I bought a Sigma 17-50 HSM OS whilst awaiting the repair of my 16-50 SDM.

The Sigma is a good lens, sharp, great OS. I now have a new 16-50 SDM and the Siggy is on the shelf.

Best regards

The Tamron is a good lens. My copy has no focus problems and is sharp from f/2.8, the focus ring is fine and smooth and the build quality is good, certainly better than the Pentax kit lens & equal to the older (non-OS) Sigma 18-50.

The biggest problems with it are the exposure inaccuracies. Mine requires a minimum of +0.7 exposure compensation but often needs up to +2, depending on conditions & aperture.

I would recommend it as long as you shoot RAW, because exposure adjustments will be needed on many shots.

BTW, I´ll post this in the leads to deals section, Jacobs seem to have it now for 240 quid, which is a real bargain: http://www.jacobsdigital.co.uk/p-38321-jacobs-digital-tamron-17-50mm-f28-xr-di-l...

Ironically as we were just discussing the build quality of the Tamron, the zoom ring on my has just slipped out of position and stopped working. I'm going to have to return it under the warranty.

Thanks everyone, I was leaning towards the Sigma, but after Jonathan's post I decided that the Jacobs deal was just too good to miss (thanks for that Jonathan!), so I've gone for the Tamron (with a 5 year warranty!).

At that price if I don't like it I think I could still sell it on and not loose too much and get the siggy. If I keep it I have a bargin!

Best

Nick

PS if anyone did want a DA*16-50 Mifsuds have a brand new one, 12 months warranty, £549, which is less than the Sigma - how times change! I'll also post on deals.

If it is anywhere near as good as my Nikon fit one you will be one very happy guy.

BTW what is all the deal with the not so good rep of the 16-50? Is it not the same design as the Tokina 16-50?

It's the same just as the 50-135, 100 macro, 10-17 fisheye and 12-24

Thought so and thought the Tokina was not a bad lens. Course when you can get the Tamron which is excellent apart from construction for less than half price the choice for most people is clear but still.

Indeed "but still"
The DA*16-50 & DA*50-135 are a wonderful combo together, i don't want to trade those.

While I really liked the idea of the DA*16-50 what put me off was that for every review or post that says its great, there is one that says that the SDM fails and the image quality is only OK, or inconsistant between samples. I also had a Tokina ATX Pro 70-200 2.8 and it was a disappointment.

The reason I was going towards the Sigma is that dispite the price, the two EX's I have are great and I really like the feel of them. But my Tamrons also been good, and common sense put in a quick appearance!

I'll let you know when I get it!