(Answer) (Category) Digital Photography FAQ's : (Category) Canon EOS-300D / Digital Rebel / KISS Digital FAQ : (Category) New User Questions :
How do I know if my camera and lens are having autofocus problems?
When combined with certain lens, the 300d will front focus or back focus. This means the camera either focuses in front of where it should or behind where it should. This varies camera to camera and lens to lens. For example, I had a 50mm f/1.8 MK II lens that badly front focused. I got another copy of the lens and it focused correctly.

Canon specifies that the focus should at least be within the Depth of Field. So the point of sharpest focus may not be exactly right but it should still look sharp when printed at reasonable amounts (like an 8x10).

You can often spot problems like this in people shots made with a camera lens that is wide open. If you focus on their eyes, the ears might be in better focus (back focus) or their nose (front focus).

There are many faulty ways of testing this with slanted rulers, etc. I suggest you look at this site:

http://www.photo.net/learn/focustest/

I personally test my lens when I get them, make sure they are right, and then stop testing. Did you get the camera to make lens tests or to take pictures?

(RP)

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