jt354 wrote in post #16647500
For the first shot I did use center focus, AI servo with the back button on my 60D - the shutter button is set to meter only. I took a series of ~8 images, all had the same issue despite refocusing for each one. What I find strange is that there are elements of the image (branches, leaves, etc.) both behind and in front of the subject, and none of them are in focus. Unless there's severe front-focus going on here, idk what happened. Since I wear glasses and shoot a crop camera, I really can't confirm accurate focus using the viewfinder unfortunately. Also, I don't use VC on my tripod; I was just testing it out because the loud VC-on "click" and image jump in the viewfinder seemed strange to me. People say it's normal for this lens though.
I don't quite understand your setup. First, I don't use the back button for focus so cannot speak in that regards. However, Al Servo mode could be part of your issues. Because it continually refocuses the lens automatically, even with the slightest of movement. It may also continuously refocus when having difficulty (lighting, contrast, etc). I'm not sure what you mean you "refocused' the lens each time when that would have been occurring automatically?
Anyhow, I used to shoot a lot of tennis tournaments and I never used Al Servo for a number of reasons; mostly because I learned that One Shot mode got me the highest percentage and sharpest images by far. Of course you have to refocus a lot but that's easy.
Try the following in good lighting, so you can maintain a higher shutter speed (1/250 +), using a fixed target.
1) Center Focus with One Shot mode. You should be getting sharp images hand held no matter with VC turned on.
I doubt it is a radical front or back focus issue because if that were the case, none of your images would ever been in focus including your second image.
2) Mount your camera on a tripod and take a picture at an extreme angle (45% or less) to a newpaper or magazine article, with use of a wide aperture and release cable or timer. Focus on one letter and then review the results. If the letters in front or back of your target letter are in better focus, then you may indeed have a front/back focus issue. You may want to try another test method as described and found HERE.
Let us know the results and your exact setup...