Problem with my 400D ?

[tigre64]

I appear to be having a problem with my 400D,
not sure if its me or the camera !!!!

When "one shot" is selected in AF mode, pictures appear to be slightly OOF
however when i put it in to "AI Focus" pictures are much sharper,
i've tried 3 lenses and appears to be the same throughout.

any ideas if this a camera issue or a technique issue
and shutter speed is much greater than that of the focal length

TIA

 

[neil_g]

are you or the subject moving?

AI focus will track the subject if it moves (as long as you hold the focus lock)

 

[tigre64]

subjects are static
i'm trying to be static :|
think i probably need to try with tripod to make absolutley sure.

 

[coldpenguin]

What depth of field/aperture? And are you using all focus points or just the centre?

 

[tigre64]

tried 5.6 and 8 and just using centre point for focus