So, I was having AF problems with my Sigma 50mm that I couldn't totally fix with MA. If I MA'd it for close distance, then AF with distant (> 8') would be completely off.
I sent it into CRIS on 9/29. They replied back with a "Per the factory, we are scheduled to receive the parts on 11-06-09. Once the parts are received the unit will be given to the tech with a rush request."
I just received the lens back today (11/5) with:
REPAIRED HSM (HYPER SONIC MOTOR)
REPLACED MAIN PCB/FPC
ADJUSTED OPTIMUM FOCAL RESOLUTION POINT TO MANUFACTURERS SPECTIFICATIONS
After some initial testing, it is behaving much better than before. Far and near AF is working great. I will do additional testing, but this is much better than before. I was ready to throw the lens away after a baby shoot earlier this year when most of the shots were unusable.
So, it looks like it was a hardware fix. This is the first time dealing with CRIS/Sigma warranty, but they were very easy to deal with.
Glad to see some good news on this. This is a topic/lens/repair facility that seems to generate quite a bit of heat when it comes up, nice to see the positive expericences get documented too. CRIS is in my neck of the woods, and I've recommended them before, so it's good to see those recommendations on the mark for others as well.
My previous copy got the same treatment.... however mine did not really show a lot of improvement... So in the end my dealer gave me a brand new copy (my third one) which is much, much better
(kudos to my dealer btw, I already had that second copy for about 5 of 6 months and was never happy with it)
I wonder if they did some major revision with the PCB/Software? or an update to the motor? I've been reading that newer produced Sigma 50/1.4's in the retail channel don't exhibit the bad focusing they used to.
bluetsunami wrote:
I wonder if they did some major revision with the PCB/Software? or an update to the motor? I've been reading that newer produced Sigma 50/1.4's in the retail channel don't exhibit the bad focusing they used to.
Yes, that is what I would assume from the communications with CRIS and the report I got back.
That would make sense because MA wasn't working for me and I've heard simple calibrations weren't working for a lot of folks.
I purchased my Sigma around July 1 of this year and I was hoping it would AF correctly out of the box. It didn't. But I'm happy now.
Did you have to send in the body with it? I just got my lens back and I am still having the same problems you did. Set MA for front focusing adjustment from about 7 or 8 feet away and anything over 7 to 8 feet would backfocus.
