Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
02-20-2010, 04:28 PM   #1
New Member

Join Date: Dec 2009
Posts: 3
DA* 50-135...chasing focus issue

My 2 year old 50/135 has started doing some weird back/front focus stuff.
Most of my shots were appearing to be OOF so I tested for FF/BF.
Testing on a tripod w/remote and SR off, at 135mm I found that I had to set AF adjustment to +7 to get a sharp in focus shot. Tried this from f2.8-4.5 and it was consistent. Distances tested were 30 ft and 15 ft.
I took several pictures in bright daylight and they were all in focus. From 3.5 ft thru 40 ft they were all fine.
Then while taking pictures in shade I found they were all OOF again. So I tested in the shade and found I had to set AF adjustment to -8. this was also tested at 135mm, f2.8-4.5 and distance of 4 ft. day I am taking pictures in sunlight and they are OOF again! This time I just adjusted on the fly and at AF adjustment +9 they were fine.
This is on a K7. I've tried 3 different fully charged batteries and cleaned the contacts.
On K10d I cannot get any in focus shots unless I focus manually.
I have a Tamron and Sigma lens that both focus fine so I am inclined to think it is the lens.
If anyone else has experienced something similar I'd appreciate their input.
Thanks in advance.

02-21-2010, 09:02 PM   #2
Senior Member
tlwyse's Avatar

Join Date: Aug 2008
Location: Waxhaw, NC, USA
Photos: Gallery | Albums
Posts: 209
Just wait until your SDM craps out with that lens and your focus issues will disappear.

My 50-135 started acting up after about 7-8 months (wouldn't work for a few minutes and then would "wake up" and work the rest of the shoot).....went to use it last month and the SDM appears to completely dead now...2 months out of warranty. Sucks.

I'm now on a mission to AVOID any Pentax SDM-equipped lenses, even it means turning to 3rd party lenses. Thoroughly disgusted with my Pentax gear right now.

02-22-2010, 09:09 AM   #3
New Member

Join Date: Dec 2009
Posts: 3
Original Poster

Thanks for the reply. Sorry to hear about the issues.

For this lens I'm trying to get feedback on sending it for service, which is what I think it needs. While I tried to eliminate any error on my part, I am a novice - hence my post.

I wasn't really aware of the SDM issues until I started forum scouring looking for a problem similar to mine. If nothing else Pentax needs to acknowledge and address the concern. Either with data to show an acceptable failure rate, or with a solution.

The DA*60-250 I was leaning heavily toward getting, I am now hesitant about. I can't afford $1,000 for a disposable lens.

  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
adjustment, af, focus, ft, k-mount, lens, oof, pentax lens, pictures, shade, shots, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
K-x focus screen drawing & Travor focus screen issue xjx Pentax DSLR and Camera Articles 2 06-06-2012 10:13 PM
F 70-210mm Focus Issue steve_tb Pentax SLR Lens Discussion 3 08-04-2010 06:40 PM
DA* 16-50 Focus Issue tigershoot Pentax SLR Lens Discussion 4 12-05-2009 02:35 PM
50-135 issue? silent_eyes Pentax SLR Lens Discussion 12 08-25-2008 01:17 AM
Any Known Quality Variation issue with DA* 50-135? gkopeliadis Pentax SLR Lens Discussion 2 08-01-2008 09:30 AM

All times are GMT -7. The time now is 03:11 AM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]