Sigma lens problem

[kwacker-snapper]

Hi i have a 70-200 sigma that seems to have developed a problem focusing, on some fixed items its fine on others its constantly trying to focus with the focus light flicking continously, i have tried it on 2 cameras and the same problem, any ideas?

 

[Orville]

Check whether the contacts are clean and whether manual focus feels tight. If MF feels good you may have an AF motor issue. Otherwise it could be a loose element.

 

[kwacker-snapper]

cleaned the connections, will try the manual focus see how that feels

 

[tdodd]

My Sigma 120-300 developed a fault where the AF would just jitter/shudder when shooting at distances under around 20'. I don't know if your problem is the same, but mine needed a repair by Sigma to the "MR Sensor".

 

[kwacker-snapper]

mines a similar fault but over longer distances, what sort of cost was that?

 

[tdodd]

My repair was covered under the three year UK warranty. No idea of cost as I did not pay. If you Google for "Sigma MR sensor" you should find other examples, but I imagine the cost might vary with the lens model.

I made a video to demonstrate my problem. I'm afraid the video production quality is poor, but you might be able to determine if your fault is the same.

[YOUTUBE]25f2qF9QSJI[/YOUTUBE]

 

[kwacker-snapper]

thanks that helps

 

[joker2006]

I had a similar issue with my 70-200 2.8 sent it away to sigma and they fixed it for £60 inc return postage All done within a week as well

 

[rhonddaboy]

If you go on the Sigma web sit there is a list of costs for repairs.