Anyone had to send in a sigma lens for recalibration?

[Thomp]

So I purchased a sigma 10-20 4-5.6 about a month ago. After using it for a bit it seems to have a decentering issue, the sharpness of the left side is looks pretty off to me. Anyway, the store I purchased from won't let me return it telling me its now sigma's problem, which means dealing with CRKennedy. So I've called them up and they want me to send in both my body and the lens.

Now I'm not willing to go through the trouble of sending in my body as well. From all the threads ive read about the 10-20 and decentering (and there are heaps) the issue has been fixed with replacing the lens. From my understanding, decentering occurs when the elements within the lens are not aligned properly, so I fail to see how this has anything to do with my body.

Has anyone had a similar experience? Did you have to send your body in as well? Any other possible ways I can get it fixed?

Argh, I'm just so frustrated!!!:angry0:

[kiwi]

I would talk to the store manager, "Anyway, the store I purchased from won't let me return it telling me its now sigma's problem"

It's certainly their problem, they sold it to you.

[B D H]

I went through the whole CR Kennedy thing, they took my 7D as well as the sigma 50 F1.4 for a bit over a week - the bottom line - it was worth it, the lens performs really well & CRK were pretty good to deal with too

If you're not too far away from Mascot, Sydney, you can drop it in personally to avoid all of the freight hassles

full discussion thread here: http://www.ausphotography.net.au/forum/showthread.php?t=58675

[I @ M]

Thomp, the main reason that they want the body and the lens is so that they can check your body with one of their own lenses that is known to be accurate. The lens that they use might not be a 10-20 but by fitting it to your body they can then look at the images and be sure that your body hasn't got a warped or damaged lens mounting surface. If your body checks out OK then they will look at the lens and see what is amiss there.
They are being entirely fair to both themselves and you by going down that path and unfortunately seeing as we don't live in a perfect world we just have to put up with minor inconveniences occasionally.

[R1titan]

Are you able to post a sample showing the left softness from the said decentering?
I would send it to CRK too, its well worth it should you intend to use the lens. btw, its only optional to send in your body too...

[Thomp]

kiwi, yep I just had a talk with them again and they were much more helpful this time, so apparently they will be contacting me soon regarding what I can do...

BDH, thanks, well it certainly sounds like the experience wasn't too bad then!

I@M, thanks for the explanation, it certainly makes sense even though I'm quite sure its fully a lens issue. But what can you do.

R1titan, give me a sec and I'll upload a couple. Well I asked the guy I spoke to specifically if I needed to send in the body and his reply was yes.

[Thomp]

Straight conversion from raw to jpeg, in camera settings were set to faithful.

100% crop of the center

http://farm5.static.flickr.com/4119/4800388461_7a5744dd42_b.jpg

100% crop of the left hand side

http://farm5.static.flickr.com/4078/4800388341_678f7d69ae_b.jpg


And a link to the full sized file
http://www.flickr.com/photos/thomp88/4801021698/

[Regnis]

I had to send my sigma 50 f1.4 in... came back perfect..however I did not have to send my body in

[Thomp]

Figured I'd provide a little update here.
Ended up having to send it in to CR Kennedy for calibration, body too. Nothing but positives to say about them, service was great, nice and friendly!
Took about 10 days which was I think is pretty quick. Most importantly...the lens now rocks! The sharpness is now consistent throughout the frame. :th3:

[Kym]

The reason they often need both is this...

Everything is made to a tolerance lets say +/- 1%.
If the body is at the limit of +1% and the lens is at -1% the total error is 2%; pretty basic but it makes sense.

[crafty1tutu]

I bought a Sigma 70-200 mm 2.8 lens whilst overseas and I think I bought a dud as I have had auto focussing issues since taking about 50 photos. It has been back to C.R. Kennedy 6 times and back to Sigma, Japan once. Since coming back the auto focus worked for around 25 photos and then stopped again. You can hear the motor whirring but it will not move. Through all this C.R. Kennedy has been marvellous and are at a loss to know what to do with the lens. I would like a replacement and they are looking into this with Sigma, Japan at the moment. They say that thousands of this lens have been sold and they have never heard of problems like this, so obviously I bought a faulty lens. I did send my camera away with the lens at one stage and although it took around 4 weeks for it to be returned, it was couriered to the door without any problems.