Sigma 500mm f4.5 + 50D Autofocus Problem (1 Viewer)

[falconer2406]

Hi all recently purchased a second hand Sigma 500mm f4.5 and am having serious problems with it on my 50D body. The lens /body combination flatly refuses to autofocus no matter what i try. I contacted the seller who told me i needed to switch to manual focus give the focusing ring a twist and then switch back to autofocus and this will connect the two together and in fairness it did initially seem to get it working.
However i switched the camera off and now when i switch on again nothing i do can get it to work. The seller has shrugged his shoulders and walked away stating that he has taken 100,000 photos in three years with the lens on a 1ds without a problem
I have several other Sigma lenses and also a 350D body and all combinations work flawlessly so i therefore rule out a body issue. I have also tried my 50D on a friends 500mm identical to mine and it works fine but his body (40D) doesnt work with my lens?
Has anyone any ideas at all, any help or advice would be greatly appreciated.
Keith

 

[GYRob]

can only sujest a good cleaning of the contacs on the camera and lens .
Rob.

 

[falconer2406]

can only sujest a good cleaning of the contacs on the camera and lens .
Rob.

Tried that thanks, cant be the body as it works with all my other Sigma lenses and also with a friends Sigma 500mm his 40D doesnt work on my lens, so in my humble opinion it has to be a lens issue?

 

[nsclayton]

Is it the newer EX version of the lens or the older APO version Keith.

 

[falconer2406]

Is it the newer EX version of the lens or the older APO version Keith.

Hi Nick, Its a Sigma 500mm APO EX HSM but its not the newer DG version.

 

[dabut101]

i had a sigma apo 70 300 on a 400d and all worked fine and then like you it would not auto focus but lucky enough i took it back to the shop and they confirmed it was the lens at fault so changed it for me although it was second hand

 

[nsclayton]

Hi Nick, Its a Sigma 500mm APO EX HSM but its not the newer DG version.

I was just checking it wasn't one of the old non-EX ones that have a known problem with working on digital cameras, yours isn't one of these and should work OK.

 

[a.dancy]

My 500f4.5EX works fine with my 50D.

 

[falconer2406]

Just to close this off, it turned out to be a faulty HSM in the lens.
Found a guy in Hitchin in Herts whom is replacing motor for £190 all in which seems a great price as next nearest quote was over £300.
Thanks to all you whom replied

 

[GYRob]

well it should give a few good years once fixed and not to bad at that price.
Rob.

 

[a.dancy]

As far as I am aware Sigma do not have any authorised repair agents. A new HSM for the Sigma 500f4.5 recently cost me #180.00 inc VAT. Always best to send to Sigma in my view.
Good luck with your lens.

 

[nsclayton]

As far as I am aware Sigma do not have any authorised repair agents. A new HSM for the Sigma 500f4.5 recently cost me #180.00 inc VAT. Always best to send to Sigma in my view.
Good luck with your lens.

If you considered this the best option Keith Sigma's service center is based at Welwyn Garden City which is only about 30 miles from where you live.

 

[andy pryce]

Yes had to send my sigma 80-400 off last year,they had a set price for repairs,it was sent off to Japan they had to change the zoom barrel,cost me £125 but came back as good as new,and a lot sharper at 400mm than when i sent it off

 

[Tim Taylor]

I had problems with the HSM twice with one of these lenses - I only got charged once though as I successfully argued that the original repair must have been faulty. A great lens apart from that glitch. :t: