It’s one of these pictures again. I’m struggling with the Tokina wideangle, I just think it behaves very erratically. The first time I had the Tokina lens (with the 40D), I had no problems with whatsoever, that’s why I liked it so much. But now… at first I thought that there’s something wrong with the autofocus because it seemed that the pictures were sharp in the wrong places. I tested it, couldn’t reproduce the issue, and concluded that the lens just is a bit on the soft side but nothing worse that a little sharpening in LR won’t fix. Then I used the lens some more and thought that it’s a bit more soft on the left side than on the right, which made a bit more worried because coincidentally, the Canon normal zoom is also softer on the left than on the right. But then I shot this frosty window and if it’s softer on the left side, then it’s very marginal.

Last night I was out shooting aurora. I had checked the infinity focus on the lens beforehand so I knew where to set the focus and I was very happy with the aurora, it was a great show and definitely worth while to drive out and stand in the cold in the middle of the night. I came home and looked at the pictures and they are all soft. As in, unacceptably soft, beyond anything that any sharpening will fix. Huge disappointment! But a few weeks ago when I did some night shooting, I also used manual focus, set to infinity, and those pictures came out sharp (not sharp-sharp but within my tolerance limits when shooting with high ISO). So, I really have no idea what’s going on. Could it be the cold weather that changed the infinity focus point? It was colder last night, and I was out much longer so the camera and lens had time to get more frozen. On the other hand, this is an extreme wide angle. There should be enough DOF to cover such changes, even when shooting wide open.

In any case, this is really annoying. More testing is needed but it’s so freakishly cold at the moment that I don’t have the patience to set up a controlled test shoot.

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