Fixing the infinite focus on a Super Takumar 24mm ...
A few months ago i bought a Super Takumar 24 f/3.5 in minty conditions for a few bucks. The lens was really clean and i noticed no faults, but, since i hadn't my camera with me, i didn't test it immediately ... Little mistake, because, although it performed really well on close focus subjects, i noticed a lack of infinity focus on landscapes. So, after logging on one of my preferred forums, i asked for some help on fixing this, and got two replies really interesting from glasbak and Just1moreDave, i decided to try my second lens surgery (the first one was on a Carl Zeiss Tessar 50 f/2.8) ...
The intervention succeeded, so, just in case someone other would have a Takumar with the same symptoms, here are the detailed instructions.
But, be warned before you start:
I ASSUME NO RESPONSIBILITY IF YOUR LENS BECOMES USELESS AFTER THAT
The surgical team: a basin cap (possibly brand new), a pair of tweezers, a precision flat screwdriver, some adhesive tape, a clean workbench and ... a camera for testing.
At first, the front name ring must be removed. I used a brand new basin cap, much more cheaper that the dedicated rubber tool. Be sure that the filter thread is clean before proceeding (eventually, you can use a toothpick and/or a droplet of WD40) ...
Applying the tool to unscrew the name ring ...
Name ring removed, time to remove the filter ring unscrewing the three screws inside (not shown, i would have needed a ring flash) ...
Putting a mark using adhesive tape, just in case it would be needed later ...
Filter ring removed, now starts the fun ...
Note the focus position, the lens MUST BE focused on infinite ...
After unscrewing a little (no need to remove) the three screws that bind the focusing barrel to the lens, the barrel becomes loosen, so i slightly turned clockwise - Be careful: my lens needed this, but your may need turning counter-clockwise ... Now the focus mark is on the "3" index - but this is not a rule of thumb: the amount of shift may be different, since this when you do "try-and-adjust-again" ...
Now, the real fun: just screw in only one of the three screws, mount the lens on a camera, take some pictures, and check crops for infinite focus. If you don't get it, just unscrew a little the screw you fixed, turn the barrel again, and do another check ...
After 3 hours spent on finding the right turn angle to get infinite focus, the filter ring is screwed in back ... Note that the marks no longer match: it's normal, since the barrel has been turned ...
Surgery finished, rings mounted back, lens as new ...
And the final result:
More shots with this great lens coming soon ...
All pictures taken with my K10D with kit 18-55 lens and a Metz 45 CL-4 Digital for lightning.
Note added the 12 October 2008: As kindly reported in the comments to this post, this technique works also with the Super Takumar 50/1.4. Moreover, i have been able to fix an SMC Takumar 50/1.4 this way, and another user from a manual lenses forum did the same with its Takumar 35/3.5.
Labels: Metz 45 CL-4, Pentax 18-55 AL, Pentax K10D, Repair, Super Takumar 24 f3.5
posted by IndianaDinos at 3:52 PM
33 Comments:
This worked great for me on a Super-Takumar 50mm 1.4. Thanks for the info and clear instructions.
TP
Hello, glad to see that this has been helpful to someone ... I, too, just fixed and SMC Tak 50/1.4 this way ...
Thanks for your comment.
I tried it on my 55/1.8 and got some improvement..no home run
Did wonder's for my takumar 50/1.4 Thanks better than the 55/1.8. I now have nice in-focus night pictures. God bless!
Hello HT,
Nice to ear that this worked for you too ...
Thanks for visiting and your comments.
This also worked for me on my 35/3.5 Super-Takumar.
Hello orly_andico,
Many thanks for sharing this useful info ... I think i will make another post listing all the Takumars that may be fixed this way ...
Thanks for commenting
I don't understand why you're going to all the trouble of repairing these lenses. If you use the proper K mount adapter for M42 lenses that fits flush with the camera body you achieve infinity focus. I have a Super Takumar 55mm f1.8 and a Takumar 135mm f3.5 that work perfectly with this type of adapter:http://www.bhphotovideo.com/c/product/97561-REG/General_Brand_ABPKS_Pentax_K_Body_to_Universal
Hello Caeidt,
Just replied in the other post ...
Fixing only the lenses that needed to, because someone adapted them to a camera with a different register distance (or simply because someone tried to clean them and failed to properly mount them back) ...
Just a note that I took the front name ring off a Super Tak 50 f/1.4 simply by using the eraser portion of a pencil. The eraser had enough grip to unscrew it.
Hi Toby, sorry for the late reply, but thanks for the hint ...
For those of you who have tried this on the SMC 1:1.4/50mm, what size screw driver did you use? When I get the name plate off I see three tiny phillips screws. I can't seem to get a grip on them with a #00 phillips driver.
thanks!
PK
ahh, Nevermind. Looks like whoever had the lens apart before had liberally applied some kind of thread locker. I've got it apart now!
Hi,
Glad to see that you were able to fix it ...
Thanks for your interest here and for commenting ...
YES! finally set my Super Takumar 3.5/24! It only had focused to about 2 meter. Now it doesn't look as beautiful anymore, but I hope it focuses right, see: http://www.flickr.com/photos/kuuan/4915791562/#/photos/kuuan/4915791562/lightbox/
Thank you so much for your instructions IndianaDinos!
kuuan - Andreas
Hi Andreas, glad to read that you have been able to fix your lens ...
Thanks for reading and commenting ...
Where I can buy the basin cap? do you know the online store which sells it?
Hi Dr Faustus,
The cap is manufactured by Wirquin. It is available on this page in the Drainage section at the bottom of the page, under the label "Universal plug".
Unluckily, i don't know if they sell it online, you should check if there is a distributor in your country.
Otherwise, if you get the principle of operations, you could try to find something equivalent ...
Hope this helps ...
Followed your tutorial. I have a Mir-24H with similar infinity focus problems - not quite the same set up but has three screws that seem to be doing a similar job.
Will try tomorrow - too late to start tonight - might yet add a Russian lens type to your list.
Thanks for your patient explanations.
TC
Hi Tom, glad to see that it seems to work for other lenses too ... I would be really happy if i could add a new lens to the list ...
Let me know how it evolves and thanks to you for spending your time here and commenting ...
thanks for all the help - just fixed my 50 1.4. I can focus beyond 3 meters now.
Hi creosote, glad to read it worked for you too ...
Thanks for leaving your feedback here ...
Dude,
Thanks for the detailed instructions. I used it to readjust infinite focus on my ol' Tak 50 1.4. Got it just right and in 10 minutes.
On the old TAK, the three screws to undo are on the Brass colored ring.
Cheers
Hi, thanks to you for spending your time here and for your feedback ...
Glad to see that these notes are useful to other people ...
Thanks so much! It worked very well for my Takumar 50mm 1.4...
Thank you for the guide! However I can't get my Takumar 55 1.8 to focus to infinity. Even if I remove the focusing grip and try turning the lens further towards infinity it just stops. It appears the helicoid's thread runs out so it stops. Is there a way to adjust the helicoid aswell?
Can this be done for Nikon F mount cameras too or just for Pentax? :)
Worked perfectly for a Pentax K 28 f3.5 too!
This is an excellent lens but annoyingly it never quite got to infinity - all sorted now.
Thanks for posting the fix!
Thank you for your help. I have managed to fix all my tacs with your method
well, it doesnt work..and how could it? when you just take off the filter ring and loosen the three screws of the focussing barrel but dont change the position of itself ( it's brass ring, seen from above) that only changes the indication mark, not the actual barrel..
Also 200 mm f3.5 ?
I just tried this on Super-Multi-Coated TAKUMAR 1:3.5/135mm
I barely managed to adjust it. I adjusted it to fit a Nikon F dslr with m42 adapter(those cheap $2 ones on ebay. So the m42 has flange distance of 45.46mm, Nikon F has flange distance of 46.50mm, the m42 adapter adds 1mm flange distance.. so in total in order to achieve infinity focus I have to adjust any m42 lens for 2.04mm of flange distance(i.e. move the whole lens assembly 2.4 closer to the sensor. I did not use any tape or anything like that to mark, having decent calipers allows you to be more precise, measure, calculate and adjust exactly the necessary amount without having to test the lens. Anyway, when doing all of this I found out there is a limit of how much you can adjust, If you rotate the focus barrel too much then after you tighten the screws you won't be able to return it to the infinity mark because it hits something and can't move any further. So I rotated it just so it can rotate fully(to the infinity mark) after tightening. After measuring that's 2.03mm, not to mention that this is not the only limitation. Another issue is when I went to put the filter ring back it prevented the the focus ring from rotating to the infinity mark again, looks like there is a physical limitation and the filter rings hit somewhere too. To fix this I loosened the filter ring screws, put the focus ring to infinity and slightly tightened the filter ring screws. The filter ring is a bit wobbly after this but when you screw the name plate back it keeps the filter ring from wobbling. Also note that the when adjusting the focus, and go beyond the amount that was infinity mark(prior to adjusting) the focus ring doesn't rotate as smoothly, a bit of grinding is felt. After all of this I don't think I reach true infinity but it's close enough and much better than having to use an adapter with glass or just using the lens as previously(no infinity at all).
Moral of the story, the lens lave a limited amount of adjustment, if the flange distance you're trying to compensate for is too great you may not be able to adjust the necessary amount. For the lens I did, that's about ~2mm or less or possible adjustment. Another thing is that this obliviously moves the lens assembly closer to the sensor so for lenses that already have the back element risking hitting the mirror you may want to make sure that adjusting won't result in the back element hitting the mirror and damaging your camera.
I'd be cool if anyone who did this successfully posts how much flange distance they compensated for so we know what's the possible amount of adjustment for each lens.
idk how to edit my post, in "move the whole lens assembly 2.4 closer" 2.4 should be 2.04
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