Sunday, January 14, 2007

Another disappointment from Sigma

I tested antoher Sigma lens yesterday in the ZOO, the 70-200 2.8 Macro. And it was just one more Sigma lens with frontfocus issues. I tested 9 Sigma lenses in the last few months and only 5 were without AF issues. Here's a short summary:
-18-200 for Canon: ok
-17-70 for Canon: ok
-50-150 for Canon: minimal frontfocus (but unusable at f2.8 in the 100-150 range on close focusing distance (headshots etc) - because of the shallow DOF, where frontfocus is more visible, image is unusable)
-10-20 for Canon: ok
-70 2.8 macro for Nikon: ok
-300 2.8 for Canon: frontfocus
-8 mm f3.5 circular fisheye for Canon: ok
-30 1.4 for Canon: weird AF issues (read the complete review for details, posted a week ago)
-70-200 2.8 Macro for Canon: frontfocus

It's really a shame that 70-200 2.8 Macro has frontfocus issues, because it's tack sharp at f3.2 (very few Sigma's are). Here are a couple of samples which came out ok (tested on Canon 350D):

f3.5. 1/500, ISO 200

100% crop from the photo above

f3.2


And this is the focus test. I focused on the line below number 50. Frontfocus is quite pronounced (f2.8, 200 mm):