Trouble with a Takumar 135/2.5

Wheatridger · Posted: Tue Feb 02, 2010 6:15 am Post subject: Trouble with a Takumar 135/2.5

I'm happy to find this group on the web, full of others who know that the real pleasure of 'digital' photography belongs to the fingers of the left hand. Manual focusing is like playing the guitar: the right hand makes the noise, but the left hand sets the note!

I've been starting a modest collection of M42s to experiment with on my KM7D and Sony A700 DSLRs. Last weekend's hunting and gathering expedition in Colorado Springs unearthed a Super-Tak 135/2.5 on a dusty, neglected shelf. I took it home for $35. The lens was in EX- condition, only a little paint wear, but with clean glass, smooth operation and no impact marks.

Only one problem- it won't focus to infinity. Set at the infinity mark of the scale, I'm getting good focus at about 15 feet. That's on either camera, using an adaptor that works fine with three other M42s I've tried. Maybe this lens would best be used on an extension tube, for closeups? I'll always wonder what happened to the focus, though. Anyone else ever experienced this bug, or know an easy fix?
_________________
Yes, I've gone digital. It's this autofocus gimmick I'm not sure about...

luisalegria · Posted: Tue Feb 02, 2010 7:23 am Post subject:

Is its seating flush with the "flat" on your adapters ?

It may not be screwing in all the way.

Alternately, its possible that there is a problem with the helical mechanism. That does happen even with Takumars.
_________________
I like Pentax DSLR's, Exaktas, M42 bodies of all kinds, strange and cheap Japanese lenses, and am dabbling in medium format/Speed Graphic work.

no-X · Posted: Tue Feb 02, 2010 8:53 am Post subject:

Yes, Takumars won't screw-it completely when using some flanged adapters. Another possibility is that the lens was unprofessionally serviced and assembled in incorrect way.
_________________
(almost) complete list of Helios lenses

aoleg · Joined: 22 Feb 2008 Posts: 778 Location: Canada

Wheatridger · Posted: Tue Feb 02, 2010 2:03 pm Post subject: Probably not an adapter problem

My other lenses that work properly with this adapter include the Super-Tak 50/1.4, the Super-Tak 135/3.5 and a Vivitar 135/2.8. Then there's a Sears 300/5.5 that seems to focus to infinity, but that's not much use as the image sharpness is poor.
_________________
Yes, I've gone digital. It's this autofocus gimmick I'm not sure about...

aoleg · Joined: 22 Feb 2008 Posts: 778 Location: Canada

Wheatridger · Posted: Wed Feb 03, 2010 12:24 am Post subject: Success!!! (almost)

Well, I'm making progress. I loosened those three screws and made some completely random rotations of the focusing ring. Then I tightened the screws and found I'd landed very close to the right spot for infinity-at-infinity focus. Another, small guesswork adjustment and now it's focusing just beyond infinity. I'll keep trying to fine-tune it.

At first glance, this lens seem to have very nice properties, with plenty of sharpness and zero CA. I better be good, because it's my third 135! I also own the Minolta AF 135/2.8 macro, reputed to be one of the sharpest lenses they ever made. The Tak looks fantastic on the KM 7D, just like it was made for it-- except it focuses in the wrong direction for this ex-Nikon user.

Thanks for all the advice. Unlike most tech repairs, which require actual know-how, I guess I just needed to dive into it and monkey around.
_________________
Yes, I've gone digital. It's this autofocus gimmick I'm not sure about...