Monday, January 1, 2007

Sigma 10-20mm F4-5.6 EX DC HSM Review

This is the next in line of Sigma lenses that I've tested. And is so far my favourite (out of cca 12 lenses). Image quality is very impressive for an ultrawide lens - as most of you probably know, (ultra)wide lenses don't have a reputation of having great image sharpness. That's why I was even more impressed. At 10 mm it's a gem. Sharp wide open, both in the center and on the borders and very sharp when stopped down a bit (f5.6-8). I did most of the test shots on the 10 mm settings, because of the UWA perspective (you can do a lot of interesting, crazy things with it). Sharpness in the center is good across the whole range, however border sharpness drops a bit when you're "zooming" towards the long end. Some moderate vignetting and CA is visible at 10 mm, but in the 15-20 range it's only a minor issue. Again bare in mind that this is an UWA lens which usually have more aberrations etc. Barrel distortion is quite pronounced at 10 mm. Built quality is excellent. AF is very fast and silent (it has HSM), it has full time manual override, manual focus and zoom rings run smooth and are well damped. Filter size is 77 mm.

This lens is very usable for nature shots, panoramas, sports like snow&skateboarding (you can "blow" the skater into the sky, because of the UWA perspective), architecture and funny portraits (I messes around quite a bit with my friends). I can only highly recommend this lens to anyone who needs an UWA lens. The price is very good too.

Below are the samples taken with Canon 400D. The field of view when mounted on 400D, is equivalent to 16-32mm on a full frame camera. From the crops you can judge image sharpness (center and border) for yourself. All the samples have watermark, don't get alert - I made the test for that site and I'm the author of the photos.

F6.3, 1/100, 10 mm, ISO 200

On the sample above you can see some CA

F6.3, 1/25, 20 mm, ISO 100

F5.6, 1/50, 20mm, ISO 100

F7.1, 1/30, 10 mm, ISO 100

F4, 1/13, 10 mm, ISO 800

Below you can see two examples of how UWA perspective can be used. Train appears to be infinitely long and the sky is also "stretched":

F6.3, 1/80, 10 mm, ISO 100

F8, 1/320, 10 mm, ISO 100

If you're interested in studio part of the test (resolution chart) it's available here . All the shots were taken by Sandi Pelko. All the paramaters were set to 0 (sharpness, saturation etc), mine (taken outside) were set to the standard picture styles (sharpness 3 (on a scale 0-7, where 3 is really a normal setting). So the studio shots may seem a bit softer.

-fast&silent AF
-built quality

-vignetting at 10-15 mm
-border sharpness at 20 mm