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09-10-2011, 09:21 AM   #1
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Need Help: SMC Takumar 50mm F1.4 ~ slippery focusing mechanism

When I turn the focus ring, I need to turn it slowly, or else the focus will be sort of left 'behind'. If I turn the focus ring quickly or suddenly, it 'slip' and the optical part seems to stop moving outward (or inward), so when I reached the end of the focus turn where the lens should be infinity, it just don't 'follow'. I have to turn it all the way back to the closest focus to sort of 're-calibrating' and then turn it slowly. If I turn slowly, the optical part will 'follow' up to infinity. Apart from this problem, the lens is otherwise like new.

09-10-2011, 10:50 AM   #2
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Loose screw under the filter ring
I found out that using m42 rear cap and a rubber band opens the decorative trim ring around the front lens element just nicely.

Last edited by minahasa; 09-10-2011 at 11:01 AM.
11-18-2011, 06:57 PM   #3
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I am having the same problem with my 50mm 1.4 Takumar. Could you provide some details on how you fixed the problem?
11-18-2011, 08:00 PM   #4
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The beveled ring, with the lens name on it, unscrews via the filter threads. He used the M42 rear lens cap and a rubber band to grip it with friction. Anything that fits, is rubber and doesn't touch the front element is fair game. The filter threads need to be straight and clean.

When the trim ring comes off, you'll see three screws which hold the filter ring/front barrel on the lens. Unscrew those and take that ring off. Then your lens will look like the above photo, with a brass ring deeper in the lens and three more visible screws. These are the loose ones that minahasa tightened. They hold the focus ring you rurn to focus to the lens's focus mechanism, the brass ring. (They can be hidden by the "ears" where the filter ring mounts, so focus a bit to see them.) You can tighten them now.

You should check to see if the lens can still focus to infinity before reassembling it, as the slipping could change this setting. Put the lens on a camera and focus on an object about a couple of miles away. See if the mark on the lens lines up to the infinity mark. If the lens doesn't focus far enough or goes too far, you can loosen the three screws, slide the ring a bit, then tighten and see if it's correct.

11-20-2011, 01:05 PM   #5
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Thank you for summing it up, Just1MoreDave
11-25-2011, 06:57 PM   #6
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The adjustment possible by those three screws for holding the position of the focusing collar are precisely for allowing adjustment of infinity focus. So you'll need to do some trial-and-error so that your lens focuses to infinity, and no further.
12-13-2011, 08:45 PM   #7
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Thank you very much for clarifying how to get the lens cover off, I managed to do that but I am concerned about getting to the second set of three secrews. Is there a trick to getting the first three off and back on again?

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