Focus issue with Rebel XTI & 85mm f1.2?

[t200]

Hi guys,

I'm definitely stumped on this issue that I've been noticing, but for the life of me, cannot figure out!

So, I've been shooting with an 85mm for the past two months for headshots and they've been super sharp and have been extremely happy with the results. However, what I have noticed is, when i shoot a full body of a subject, it tends to be fuzzy/not sharp.

I'm using a rebel XTI and AF (One Shot) with a EF 85mm f1.2L USM attached.

I think the lens can produce sharp quality images, so I must be doing something incorrectly when it comes to focusing?

Anyone have an idea why this must be happening?

[Photo-John]

I hope you don't mind but I moved your post to the Canon forum. I think it's a better fit here.

I think we need a little more information. What exposure mode are you using? What focus point? Can you describe your focusing technique? Are you shooting wide open at f/1.2 in the out of focus photos or does it happen when you're stopped down, too? Any chance you can upload some sample photos for us to look at?

[wfooshee]

My first thought is an assumption that depth of field is not deep enough for you shot. If you're shooting at f:1.2 "because you can" then you ought to expect some sharpness issues. Try the same shots at f:4 or f:8 and compare.

It also depends on your focus point. If you're framed for a full body portrait and allowing the camera to focus on the center, then the focus distance may not be appropriate for the setting. For most folks, if you focused on their belly, then the face might be on front of that distance, and out of focus if the aperture is too wide. (Myself, the face would be behind the focus, but that's a different issue. ) Center the face (or select a focus sensor on the face if the camera lets you do that) then half-press and recompose. Focus-lock should come into play and keep the face focused when you move the camera down.

Also, 85mm is a moderate telefoto on that camera with its crop sensor, equivalent to a 135mm on a film camera. That will change the focus distance you need for the framing you want, which in turn may change the depth of field you expect to have.

A lot of assumptions in my answer, though.

[wedding photographer]

Shoot at f/2.8 or 4.5 at least. At 1.2 it won't be sharp at all. Try it and look at the results! You will see that the 85mm lens will be nice sharp around 2.8 and up.

[dingoodk]

Its also with me too my Camera also have same issue

[dolindo]

thanks for all the information guys