I got myself a Sigma 150-500mm around easter.
I was looking SO much forward to this step up in quality at the tele end. Then I got it, and my feelings were a bit mixed. There is the weight thing, which shouldn't come as a surprise - and in fact with the tripod-collar-handle and stabilization, it is possible to use it hand held with a bit of practise (and workout). Which is good, because in spite of all good intensions I rarely get to mount it. I use it for wildlife mostly, and most chances I get are too spontaneous for tripods - and when I do sometimes go on a proper birding trip, the good tripod is usually being hogged by our telescope...
Well then, I have been practising. It has been my most used lens the last half year. But I'm still ambiguous. First I told myself that the lack of sharpness at 500mm was due to the lens being slow, and ISO 400 being a bit noisy on my k7. Now I have a k5, ISO 400 should be spectacular, but I still get slightly fuzzy results. I have met other Bigma wielders in the field (with other bodies too) and simultaneous comparisons always show my pics to be less sharp.
Also, I find there is a bit more CA than I hoped, and the bokeh isn't exactly pretty. At least not after unsharp mask, although I try to be gentle. And without unsharp mask, everything is very wooly.
Then I worried a bit that perhaps the focus point was a bit off. But I can't seem to make sense of that either. I tried testing. I tried trial-and-error focus compensation in both directions. Nothing seems to help awfully much.
Maybe this IS all I should expect?
You guys have wonderful eyes, and there are so many clever people in here, so if you would offer your opinions, I would be very grateful. I attach a couple of great egret shots I took this morning. They are resized on flickr, cropped just slightly and given a bit of unsharp mask. I think passing them through flickr strips the exif, but they are all ISO400, f6.3, and the shutter time is 1/350, 1/350 and 1/250.
I tried focusing on the eyes, AF-S, center focus point, focus and recompose.
Last edited by MetteHHH; 10-14-2011 at 04:46 AM.
Reason: Adding a few details