Anyone use the lens calibration feature?

[nemophoto]

I just finished a week's shoot and was horrified to find that my 24-70mm, which has been excellent on my older 1Ds2 and my 1D3, seems to horribly front focus (or so it seems) on my new 1Ds3. Luckily, I caught the problem fairly early and stopped using the lens. (Interestingly, I shot an editorial immediately after with the 1D3 and the 24-70 and it was tack sharp, even almost wide open.) I seem to remember that the Mark III series has a utility or something that allows one to adjust/calibrate lens focusing, rather than ship virtually every lens off to Canon with the body.

Has anyone used this? Was it successful? How difficult is it to do, and in fact, HOW do you do it? Thanks.

Nemo

[Josh-H]

I just finished a week's shoot and was horrified to find that my 24-70mm, which has been excellent on my older 1Ds2 and my 1D3, seems to horribly front focus (or so it seems) on my new 1Ds3. Luckily, I caught the problem fairly early and stopped using the lens. (Interestingly, I shot an editorial immediately after with the 1D3 and the 24-70 and it was tack sharp, even almost wide open.) I seem to remember that the Mark III series has a utility or something that allows one to adjust/calibrate lens focusing, rather than ship virtually every lens off to Canon with the body.

Has anyone used this? Was it successful? How difficult is it to do, and in fact, HOW do you do it? Thanks.

Nemo
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There are already a few online reviews of this feature and it does seem to work very well - but I havent tried it as yet myself. In terms of how to do it - its pretty well covered in the manual.

From memory *I may be wrong* I think it was northlight images, or Digtial Camera Reviews that did a review on this feature.

It 'may' not be a front focus issue you are having with your lens - especially if the results are sharp with the 1D3 and the same glass.

I t could be that that 1DS MKIII is 'too good' for the 24-70 as has been suggested in the recent British Journal of Photography. I do not own a 24-70 to test it and cast no dispersions on the validity of the claim. But .. if you are having issues with this lens on the 1DS MKIII it might be worth picking up the issue with the review of the 1DS MKIII for a read.

[David Anderson]

The calibration feature is excellent IMO.

I've made a card with a scale for doing the test and run all my lenses through both bodies.

My 100 macro and 85 1.2 were both a little in front and an adjustment now has them sharper than ever even wide open.

It's the ultimate pixel peepers toy..

[nemophoto]

David,

How did you go about creating a "calibration card" for focus adjustment? Did you work on your lenses at all apertures, or just wide-open?

Josh,

The issue may very well be that the 1Ds3 stresses a lens' resolving power greatly, and that the 24-70 is at it's max. However, I'm inclined to think, at least based on what I've seen both qualitatively from the 1Ds2 (there were comments when that camera came out that lenses couldn't keep up), and current problems with the 1Ds3, that it may be a focus issue. Interestingly, I have a 17-year old 300/2.8 that I still use a few times each shoot, at it still amazes me with the resolving power. The 1Ds3 doesn't even begin to tax the lens.

[David Anderson]

David,

How did you go about creating a "calibration card" for focus adjustment? Did you work on your lenses at all apertures, or just wide-open?

Hi Josh - I made a graphic in photoshop and print copies of it on 6x4' photo paper and then shoot at an angle, lines down the side front & back of the focus point shot where the lens is hitting.
On Canons advice I shoot wide open and at the longer end of a zoom.

I doubt it will win any awards for design, but it works for me.

PM me your email and I'll send you a Hi-rez Jpeg of it to try.