Seriously you guys(XT /85mm back focus)

Ok I believe I have encountered my first back focusing issue.

I, like most, have never really pixel peeped or even questioned focusing.
I usually go into the proverbial field and test it out. I keep watch of focusing and sharpness and take note of any odd situations.

After shooting in different situations I (After a little over 2weeks) noticed my new 85 1.8 may be back focusing. Like any other times I question things I try to find proof. At first I chalked it up to user ignorance. But then decided to do the test. Battery test that is. Here are the results.

Now could this possibly be my XT focusing incorrectly? I did the same test other times and got the same results. I went from 1.8-2.8 but will only post up to 2.5. All shot on tripod with mirror lock using a remote switch 1/250

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the other two

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Yes, the XT can suffer from such auto-focusing problems. A few months ago, I found that mine was consistantly front-focusing and sent it to Canon for warranty calibration. If you suspect the camera, I recommend testing as many lenses wide-open as you can (and take the results from the kit lens with a grain of salt).

JackProton wrote in post #2975899
Yes, the XT can suffer from such auto-focusing problems. A few months ago, I found that mine was consistantly front-focusing and sent it to Canon for warranty calibration. If you suspect the camera, I recommend testing as many lenses wide-open as you can (and take the results from the kit lens with a grain of salt).

Well shyte, the kit and the 85 are the only two lenses I have. But you would agree there is some back focusing?

Af points?

cosworth wrote in post #2975961
Af points?

center (middle battery One Shot)

Try a different body before you send it back. I had this issue with a 300D back in the day and it was a dirty mirror...

cosworth wrote in post #2975976
Try a different body before you send it back. I had this issue with a 300D back in the day and it was a dirty mirror...

Well I just opened up my recently sold 50mm f/1.8 and had no problems, perfect focus, middle battery came out sharp and the other two were properly blurred so I would chalk it up to the 85 lens being defective.

I'd still eliminate the body before sending it back to Canon for a month.

cosworth wrote in post #2975989
I'd still eliminate the body before sending it back to Canon for a month.

good lord itll take a month?
I could call the local and ONLY camera store in Oklahoma and ask if I could test it there on another body. Also I went to Canon's site and they recommended a place about 10miles from here that COULD solve the problem, Ill give them a ring as well. Thanks for the help.

Subject distance? Check that your batteries were further away than the minimum focus distance of the lens... If so then you have a problem.

I was back nearly 4ft, I just had to crop to get in tighter on the problem. B&H says minimum 2.8'

thekid24 wrote in post #2975999
good lord itll take a month?
I could call the local and ONLY camera store in Oklahoma and ask if I could test it there on another body. Also I went to Canon's site and they recommended a place about 10miles from here that COULD solve the problem, Ill give them a ring as well. Thanks for the help.

You could also try a different copy of the 85mm with your current camera. Canon sometimes recommends sending your lens in with the camera so that they can be calibrated together. This is supposed to make certain that the specific lens will focus correctly with your specific camera rather than just calibrating one or the other to standard factory specs.Canon seems to take one to two weeks for camera calibrations of this sort.

No filter on?

Move the batteries farther apart too, (side to side, not front to back) by having them overlap, your alomst defeating the intent of using batteries (ie: individual solid objects over a sheet of paper) but honestly it looks bad.

It does look bad - but you'd be amazed at what a better body can do. My 1d was better than my 30D which was better than my XT