Auto focusing issue affects limited number of Sigma telezoom lenses

[scottthehat]

After thorough investigation, we have ascertained that some APO 50-500mm F4.5-6.3 DG OS HSM, APO 120-400mm F4.5-5.6 DG OS HSM and APO 150-500mm F5-6.3 DG OS HSM lenses, produced recently, may have a potential autofocus defect.

More on http://www.sigma-photo.co.jp/english/news/info_100616.htm

I'd look into that if you recently bought one of these.

and i think mine has it as it has just stopped af and not done nothing untill the camera has been turned off and on.:shake:

 

[Arkady]

Sigma? Problem?
How unusual...

 

[micloi]

That is old news (for the 120-400 and 150-500) and most lenses have already been rectified by Sigma (I checked with Sigma UK when I bought mine and also tested it to make sure).

As for the 50-500 though they managed to do it gain .... ;(

Also your link is not working properly!

This one is ok:
http://www.dpreview.com/news/1006/10061601sigmatelephotonotice.asp

 

[neil_g]

Sigma? Problem?
How unusual...

oh hush.. :razz:

 

[Chrisbie]

My new lens has been giving problems 150-500, serial number is in the list, first time trying a sigma, not very impressed despite knowing loads of people very happy with them. Will probably go for a refund as I still can, Or am I being a little hasty maybe?

 

[micloi]

If it is a sharp copy and the only problem is the AF then do go into the trouble and send it in as it is a good lens.

If you are not happy with the sharpness either then get a refund and buy a different copy (or model)

 

[JerryL]

So what "exactly" is the nature of the problem? Is it that the lenses are not focusing at all? Slow? what?? it isn't very clear what issue is being sorted out.

 

[scottthehat]

My new lens has been giving problems 150-500, serial number is in the list, first time trying a sigma, not very impressed despite knowing loads of people very happy with them. Will probably go for a refund as I still can, Or am I being a little hasty maybe?

how can you get a refund.

 

[Chrisbie]

how can you get a refund.

I have an agreement with the "supplier" that allows me to return it. I purchased it very recently and they have agreed to a refund.
They know though that they will get the money back off me as I am
bound to buy something else. Probably correct.

 

[Inbred29]

So what "exactly" is the nature of the problem? Is it that the lenses are not focusing at all? Slow? what?? it isn't very clear what issue is being sorted out.

After a phone call with Sigma today all they said was that the autofocus could be "intermittent" and fail to lock on the subject.

Which is pretty vague to be honest and at f6.3 at 500mm in less than perfect conditions it would do that anyway wouldnt it?

 

[Mike.P]

After a phone call with Sigma today all they said was that the autofocus could be "intermittent" and fail to lock on the subject.

Which is pretty vague to be honest and at f6.3 at 500mm in less than perfect conditions it would do that anyway wouldnt it?

My Sigma 50-500mm does that anyway and it's years old

 

[scottthehat]

sigma recon it ill take 2 to 3 weeks to fix the problem, and the problem is the lens just stops auto focusing,