Lens Choice - Fast 18-50

[Rattus79]

I'm thinking it's time I got a fast short zoom.

I'm kinda tossing up between the Sigma and the Tamron but haven't ruled out the pentax.

I guess what I'm asking is for some input as to wether the Sigma (18-50 2.8) is worth the extra $$ then the Tamron 18-50 2.8, or for that matter the extra $500ish for the pentax??

what are your experiences? the good the bad and the ugly.

[Doninoz]

Hi Greg, I don't know about the Pentax but the Tamron has an edge over the Sigma which is not acceptable sharp till F 3.5 or 4.

I have friends who have them. They go out together - same camera - Canon 20D - Sometimes the Tamron wins and sometimes the Sigma wins...same scenes.

The Tamron seems to blow up better though, as the Sigma seems to have a lot of noise around the edges (at lower than F3.5).

The Tamron is also cheaper if I am not mistaken...more money for other things!

[Rattus79]

yeah, the tammy is about $400 from fleabay and the siggy is closer to $600 where as the pentax will set you back a cool grand.

[crf529]

The Pentax is in another league with it's price, but it's performance over the others doesn't justify it.

The Sigma and Tamron are fantastic, both very sharp lenses. Some believe that the difference now'a'days is that the Tamron is a slightly sharper and cheaper lens, where the Sigma has the advantage in focus and construction.

But really the difference in image quality shouldn't be that big at all. QC on the Tamron and Sigma line has always been questionable at best, and if one lens falls behind in performance majorly, it's probably just a bad copy.

[KevPride]

Before I would buy either, why not consider the Sigma 17-70 2.8-4.0, this has an excellent reputation and is 2.8 always necessary with ISO improvements in the newer Pentax bodies. Plus its cheaper to boot.

[Rattus79]

Before I would buy either, why not consider the Sigma 17-70 2.8-4.0, this has an excellent reputation and is 2.8 always necessary with ISO improvements in the newer Pentax bodies. Plus its cheaper to boot.

I actually have one of these, I also have a 28mm 2.8 already too. My copy of this sigma is .... well ... Pathetic. I reverted to using my kit lens as it gives better results.
What i really want is to not to have to swap between my 100 mm 2.8 and the 28 2.8 constantly.

[xjjohnno]

Go for the Tamron.

[Rattus79]

Well, the Tamron is on it's way.

After looking at ebay, and talking to Photo Continental, (both of which I have to wait for) I decided that for the sake of Australian stock and Australian warranty, I could buy 2 grey market ones (well almost) for the same price.