S-M-C Takumar 50 1.4 mechanical problems

ilguercio

I just received this Tak but i've noticed that the aperture won't close down past half stop before f/5.6.
Also, i can hear a subtle click when moving the focus ring from 0,7 m to 0.8 m, it sounds like the helicoid touches a diaphragm blade.
Another thing is that i dont have such a hard stop at infinity, it looks like it's different from the end at 0.45 m.
The lens must have been dropped, the filter ring is a bit damaged but the images from the Tak look absolutely perfect.
Any thoughts?

ilguercio · Posted: Fri Mar 16, 2012 11:19 pm Post subject:

Ok, i guess i've already found the problem.
It's the adapter that either prevents the aperture lever to turn completely or doesn't fully press the pin if not screwed totally.
What should i do?

ilguercio · Posted: Fri Mar 16, 2012 11:27 pm Post subject:

Update:i tried to move the switch to MAN and i got a preset lens but as i turn the focus ring the whole mechanism makes a weird noise, like metal surfaces gritting against each other. If i set it to AUTO the ring is smooth as silk.
Then i have this problem with the adapter, any ideas?
Even if i hold the big pin down with my thumb there is still that weird noise when focusing.
If i set F16 with the adapter i can't go past 1.5m.

Found something useful:
http://www.pentaxforums.com/forums/pentax-slr-lens-discussion/135293-s-m-c-takumar-50mm-1-4-distance-scale-problem.html
This is for the clicky focusing.
The other problem was fixable by filing down the inner ring of my adapter. It was holding the pin down but was also pushing sideways onto the aperture lever. A good filing action (and a bit of sweat) did the trick. I have set the lens to MANUAL because i suspect that on AUTO the pin is not fully pressed thus not closing the aperture after the above mentioned stop.
Now i really need one of those tools to unscrew the lens assembly if i want to fix this minor issue.

ilguercio · Posted: Sat Mar 24, 2012 5:44 pm Post subject:

I did a side to side comparison between my Tak and my Zuiko and the latter seems to let more light through at any aperture compared to the former.
Can the Tak be yellow a bit or that only affects white balance?
I can't notice any yellowing but since the lens is radioactive i guess it can yellow over time somehow.
Bu the way, still haven't found a good way to unscrew the nameplate ring, the lens needs a good lube of the focus ring but i need the right tools to do it.

ilguercio · Posted: Tue Mar 27, 2012 2:46 pm Post subject:

Why can't i tighten the focus ring?
Focus was a bit loose so i removed the front part but the 3 screws are so hard to tighten.
The focus ring is slippery, i have to press it against the brass ring to focus.

ilguercio · Posted: Tue Apr 03, 2012 6:08 pm Post subject:

Solved with a bit of metal epoxy, i guess i will need some sort of hammer if i ever have to disassemble it again.
Very Happy

The lens isn't the prettiest of them all but works, perhaps the focus ring is a bit slow albeit smooth.