[Tonycog]

Hello

I was recently on a photo trip to Bosque in New Mexico to shoot the cranes. While there, I had a lot of trouble with the auto-focus of my Sigma 50-500. The lens / camera struggled to lock-on to focus throughout the week. When I returned home and looked through my photos on a larger monitor, I discovered that many, if not most of my shots with the long lens were not focused properly. The lens does not focus smoothly, whether auto or manually turning the focus ring. I am assuming that it needs cleaned and serviced. Who do you recommend I contact to get this lens checked out?

Thank you,
Tony

[aslyfox]

if there is no warranty coverage, I suggest a craftsman here in Topeka Kansas.

he helped me out when my D FA 150-450mm literally separated into two pieces

Phototronic

119 NE US Highway 24
Topeka KS 66608
785 233 0231

he was able to repair it and at a cost of less than $300

he runs a one man shop opened only in the afternoon M-F and he is not, by his own admission, the world fastest

he advises you to keep calling him to check on the progress of the repair

he does Vintage to Digital Camera Repairs with free estimates [ he does not sell equipment ]

If you want to try him out, please call him first

_______________

you should also look at this area of the forum:

Pentax Repair Facilities (Wordwide listing) - PentaxForums.com

[DeadJohn]

I dealt with Sigma's official repair center (Ronkonkoma, NY) and was very satisfied with their work and their communications. That's only a single data point, though.

[Tonycog]

Thanks to both of you for your replies. I contacted Phototronic in Topeka yesterday. He is only a couple of hours away from me. He told me that he is limited in what he can do to Sigma lenses as Sigma does not make parts available to independent repair shops. He will take a look and see if he believes he can help me with my lens. It looks like I will be shipping it to one of their authorized repair shops.