sigma lens and eos10D

[ninrood]

hello everyone

Allowed me a small introduction to my self:

I live and work in Portugal and i've done the transiction from film to digital with the eos10D just a few weeks ago. I'm not a professional photographer but i do photograph allot, mainly nature (animals and scenics)and portraits.

this is my first time in the forum and I already have a question. Not a good way to start heim :-)


I have a sigma 70-200 EX 2.8 HSM lens that works fine with several canon bodies (namely eos300, eos3, eos50). By the way, is a recent model. No firmware updates need it till now.

Recently I bought a canon eos10D body and the lens does not focus correctly. It always focus in front of the selected focus point. i.e.: at a distance of 2.5 m (central focus point, zoom at 200, f/2.8, 1/1000) of a focus target it focus 20-30 mm in front of the target.
The problem seems to get worse at bigger distances.

I've tried the same lens with other eos10D bodies but the problem persist.

I've tried the same body with different canon lens and the focus accuracy is

[topeju]

Let me start off by stating that a large number of people on this forum and elsewhere have reported that their 10D works perfectly well with their Sigma 70-200/2.8 EX.

However, I have the same problem with my Sigma 70-200: I constantly get front focus with the lens on a 10D (I've tried two bodies, my own and the one at the local camera store). I haven't yet made a proper test with my EOS 5 though (I've intended to for the last three or so months, but have just never gotten around to actually grabbing the old film body with me :) ).

On my 10D the autofocus action is also "stuttering" (for lack of a better word): the camera turns the focus (slowly!) a short distance towards proper focus, then gives up trying to autofocus and starts to blink the "unable to focus" indication. Releasing the shutter and depressing it halfway again starts the operation again and I end up slightly closer again to the correct focus distance. Repeat ~10 times, and finally AF will turn the last few meters of the focusing. With the end result being front focused. :-(

On the EOS 5, the lens does not exhibit this "stuttering" behaviour, but promptly focuses on the subject (although, as I stated above, I don't know if the focus actually is spot on the subject).

I contacted Sigma International back in May (I think) and was told to ship the lens to them in Japan for adjustment. I'm somewhat reluctant to ship the lens halfway across the world so for now, the lens has just stayed at home.

I've posted (far too many) messages on this behaviour earlier, so you could just check my earlier posts for the details. The email correspondence I had with Sigma I've posted earlier in this thread (http://photography-on-the.net/forum/showthread.php?t=10843).

[ninrood]

Thanks for your post,

topeju wrote:
...
However, I have the same problem with my Sigma 70-200: I constantly get front focus with the lens on a 10D (I've tried two bodies, my own and the one at the local camera store). ...



bad luck for the two of us :(

topeju wrote:
...On my 10D the autofocus action is also "stuttering" (for lack of a better word): the camera turns the focus (slowly!) a short distance towards proper focus, then gives up trying to autofocus and starts to blink the "unable to focus" indication. Releasing the shutter and depressing it halfway again starts the operation again and I end up slightly closer again to the correct focus distance. Repeat ~10 times, and finally AF will turn the last few meters of the focusing. With the end result being front focused. :-(


I have the same problem

topeju wrote:
On the EOS 5, the lens does not exhibit this "stuttering" behaviour, but promptly focuses on the subject (although, as I stated above, I don't know if the focus actually is spot on the subject).


On my eos 3 I don't have problens that kind of problems also and I never observed out of focus issues.

topeju wrote:
I contacted Sigma International back in May (I think) and was told to ship the lens to them in Japan for adjustment. I'm somewhat reluctant to ship the lens halfway across the world so for now, the lens has just stayed at home.


I also contacted sigma a few weeks ago but got no answer till now. Can you please post the contact to check if it is the same?

All the best,

ninrood

[CyberDyneSystems]

This clearly falls under the category of "Abnormal behavior"

I think that you should indeed send the lens in for repair or demand a replacement. :(