These are slightly off-center crops - I theorized that the variable softness on the might be due to a ridge on the paper but I cannot find it as it was taped to the wall after being smoothed out repeatedly.
As a matter of fact, I had to use slightly off-center crops just because of that.
The full images are here:
If they are off-centre crops, i'd say there's a problem...... My 12-24 is nothing like that (that i've noticed, that is) - I've never done a test of shooting a piece of paper... but it's sharp IMHO, very!
Aaron
paulhodson wrote:
It may be - but the first image you posted in particular is very soft although it sharpens up well in Photoshop.
You should know that its a compressed image at 80% quality.
The original is much better than these.
Also its was a very overcast day yesterday and this was just a quick candid with no thought of Av or Tv, just point and shoot !
I like CurtPick's advice here. It's always impossible to compare testing methodologies and whatnot. We have no idea what kind of testing setup you did here, whether you were exactly parallel to the plane of focus, was the paper flat enough, etc.
Probably the best thing to do is go out, take real pictures, review them, if they are unacceptably soft and you are unhappy, return the lens. Viola!
Make sure you test it more than once. Also, try AF versus MF. And refocus after changing settings. It's easy to mess up focus tests.
My 12-24/4 is a little fuzzier at 12/4, but gets 100% sharp by f/5.6. And all other apertures and focal lengths are 100% sharp. ("100%" meaning as sharp as mine gets, of course.)
Yours definitely performs worse than my copy, but make sure your test is valid before packing it back up!
I had a Tokina 12-24 that looked similar. Right hand side of images looked bad. I ran some tests using a large painting filling the frame, and compared the images with other lenses (Canon Ls). I found that the right side was out of focus, left side good. Optical axis was not aligned with lens mount. Tokina gave me a new lens. Took 2 weeks total.
