After many weeks of reading, and many more of saving, I finally arrived at a decision for my ultra-wide lens. Here are some of the reasons I chose the lens I did:
1) Could not get the lens I wanted: Wanted the Tokina 11-16mm f 2.8. I sent an e-mail to Tokina and asked if they might release this awesome lens in Pentax Mount--they did not even answer my e-mail. I have a vacation on the Applachian trail in early June, this ruled out Tamron's 10-24mm too.
2) What was said here was very influential:
PentaxForums.com Third-Party Pentax Lens Review Database - 10-20mm F4-5.6 EX DC HSM (AF Lens)
3) The Sigma 4-year Warranty
4) Excellent CA control
5) Review here:
Sigma Lens: Zooms - Sigma 10-20mm f/4-5.6 EX DC HSM (Tested) - SLRgear.com!
6) Really wanted 10 & 11mm focal lengths
7) Lens is reportedly distortion free from 12-20mm
8) Only need the 10-16mm reach, since I'm happy with 17mm up on Tamron 17-50mm 2.8
9) Even though money was not a factor, $425.oo shipped to my door is hard to argue with
10) The beautiful shots all over the web: for example,
Flickr: Phototraveler7's stuff tagged with sigma Full-size sample photos from Sigma 10-20mm F/4-5.6 Flickriver: Photoset 'Sigma 10 20' by Palometa Sigma 10-20 F4-5.6 EX DC 201-205 - Dyxum forums - Page 1
I've had the lens a couple of days and am honestly impressed. It is much better indoors than I thought it would be. As reported, distortion is controllable by carefully watching the viewfinder. I find the lens sharp enough, even wide open and @ 10mm, though it in no way is as sharp as my Tamron 17-50mm. On the other hand, the Sigma has more accurate colors and better contrast than the Tamron.
Also, the lens meters more accurately than anything I have used on my K20 for some reason. The AF is very quick and accurate. It comes with a hood & nice soft case. The lens exceeds my expectations. Nothing special, but here are my first shots with it--from our local Bike path. No PPing or cropping:
Last edited by Jewelltrail; 09-25-2009 at 09:09 AM.