Hi guys. Like many others , I recently had the problem where my prized 50-135 lost the ability to auto focus. One day it worked well, the next time I picked it up, nothing.
I searched for a solution to the problem, other than just sending it to CRK or Pentax and found a DIY solution that seemed promising, but I'm a big clutz and the screws in a lens are tiny. (and I finally admitted to myself that that I am no longer superman, and there are things I simply should not do)
I knew that there was a camera repair man who lived close to me and worked from home, so I looked him up. Turned out he is only about a kilometer from me - happy days.
Lets see if he can repair the lens given the DIY tutorial I had found. My lens had no warranty, and I had very little to lose other than a small fee if he could do nothing about it. It had to be worth a try.
My repair man turned out to be a small Japanese man who had been formally trained in camera and lens repairs at one of the big two.
Long story short, after only a couple of days away in hospital and a very modest fee, I now have a fully functioning auto focus lens again.
If any of the Melbourne community have a problem with SDM lenses I suggest this may be an alternative way of getting them back into operation. If you want details, please send me a PM.
The repair man told me in japanenglish that the lens was 'poor design', 'not big enough screw' (he was referring to the screw that goes through the AF motor) ,'needs screw both sides, in opposition, so as to not bind'
It looks like the torque of the lens hunting back and forth causes the screw in the motor to over tighten and eventually stop the motor from turning.
i'm a happy camper and hope this provides some clues to the problem and also a low cost, speedy solution to SDM failures.
Cheers!
Wayne
Last edited by wizofoz; 05-26-2011 at 04:27 PM.