I have a EOS600D with kit lens, the automatic focus doesn't work any more, because I disassembled the lens just a month ago. I have to use the manual focus to take the photo. Unfortunately, I found out the picture neither sharp nor perfect focused, majority of photos are fussy. For the sharpness, I think it's related to the correct white balance setting.
Sharpness has nothing to do with whitebalance. By dissasemblig the lens you have probably upsett the justification of the glass parts. There's only 1 option. Buy a new lens !
It can also be that your camera is focusing wrong. You can check that pretty easily. Use a ruler and and put it flat on a table and focus on for instance 25cm mark. If the camera is focusing right you should see that the focus is on the 25cm mark, is it on the 24 or the 26 mark, then you need to get your camera and lense for service.
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