faces out of focus-portrait photography

[tjspix]

I bought a Canon Rebel T1i and would love to use it to start a photography career/hobby. I have taken some photos of friends for senior pictures. When I got the proofs back in the mail from a professional developing company I noticed that a lot of my faces were slightly out of focus but where I had moved my focal point to was not. I did not notice this on my screen as I was editing them. I had my settings at shutter priority AE, Tv 1/160, Av 4.0, eval metering, ISO 100, lens EF-S 55-250, focal length 55, shot in RAW,external flash, FE lock off, AF mode one shot. I have the stabilizer on. My technique was to focus on the eye and hold shutter button 1/2 way down and reframe then take shot. Do I have the wrong settings or a camera problem? or a technique problem? I just had my camera cleaned and serviced about 2 months ago. Any help would be appreciated. Thank you
Tere

[AngeloDefensor]

yes face is out of focus, did u try manual focus?

[emtab]

It's difficult to tell from the size of image attached, but is there an area of the shot that it is in sharp focus? If there is an area of sharp focus, does that coincide with the active focus point? If so, that tells you that you reactivated the AF when you recomposed.

There are several reasons that you might have missed focus on these shots:
1. Are you sure that you didn't reactivate the AF when you recomposed? (Back button focusing is an easy way to avoid this issue)
2. Did you or the subject move after setting the focus? (ie, when you recomposed did you change the plane of the camera in relation to the subject)
3. Does the lens ever produce sharp shots? (To rule out an issue with the lens)

Those are the most obvious three to me... there are several others, but my money would be on either an accidental reactivation of the AF or too much movement in recomposing.

cheers,
emtab

[erinville]

I need to upload the picture but I think I need to register first for this.
How do I do this, & how do I upload?