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Message |
    
Burning_k
Tinkerer
Username: Burning_k
Post Number: 1
Registered: 10-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, October 19, 2011 - 03:39 am: | 
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I recently got a Yashica 12 and noticed that there is eiterh grease or fungus on the lense.
Found a Mat tutorial on how to clean them, but the problem is: neither does the rear lense have notches to unscrew it nor can u clean it with shutter at B from the front because there is a glass between the front lense and the shutter.
Does anyone know how to solve that problem? |
Rick_oleson
Tinkerer
Username: Rick_oleson
Post Number: 1145
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, October 19, 2011 - 04:04 pm: |
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There is not a glass between the front of the rear lens cell and the shutter. The rear cell is composed of 2 lens elements, which are cemented together. If the grunge you're seeing is neither on the rear surface nor the front surface of the group, then it has to be in the cemented interface between the 2 elements. Which, I'm afraid, pretty much means you're screwed. |
Br1078lum
Tinkerer
Username: Br1078lum
Post Number: 163
Registered: 11-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, October 19, 2011 - 10:07 pm: |
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Rick, I think he is asking about the elements in front of the shutter. If it's a four element lens, I don't think he can see how to get the second element out. I'm not much help on this either, because I've never torn down a Yashica TLR. IIRC, the Yashicor is a three element lens, and the Yashinon is a four element (Tessar) type. Depends on what he got with the camera.
So, Burning k, how about some more info, such as which lens does it have?
PF |
Br1078lum
Tinkerer
Username: Br1078lum
Post Number: 165
Registered: 11-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, October 19, 2011 - 11:12 pm: |
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Burning k, I did a search, and found that all the Yashica 12's reportedly had the Yashinon lens. So we are talking four element Tessar. And after looking at Rick's diagrams of a front teardown on a 124G (very similar), it appears that the front two elements are cemented together also, or at least mounted in a barrel together. I still haven't found a design drawing for this lens, so maybe someone else has more info for you.
Maybe you could post a picture or two of what you are looking at.
PF |
Burning_k
Tinkerer
Username: Burning_k
Post Number: 2
Registered: 10-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2011 - 12:39 am: |
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It has a Yashinon 1:3,5 f 80mm lense.
I think you're all right with the idea that it's a 4 element lense.
I took some photos and hope that you can figure out what to do now.
http://img402.imageshack.us/img402/4876/img1143copy.jpg
unscrewed front element and lense (the guy who owned it before me must have handled it a little rough)
http://img35.imageshack.us/img35/6721/img11451copy.jpg
Camera with unsrewed front element (that's the glass that keeps me from cleaning it in B)
http://img31.imageshack.us/img31/2896/img1150copyz.jpg
The root of all evil. (i hope you can see the grease) |
Brcamera
Tinkerer
Username: Brcamera
Post Number: 122
Registered: 08-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2011 - 01:55 am: |
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What has happened is that you have removed the front element from the front lens cell. The front cell is composed of two air spaced elements. At this point, I would use a rubber stopper, app. 28mm in diameter, to remove the part that is still screwed into the front of the shutter. |
John_s
Tinkerer
Username: John_s
Post Number: 60
Registered: 07-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2011 - 08:02 am: |
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Yes you have just removed the front element and retaining ring, you need to get the rest of the front cell assembly out, it usually comes out in one piece. It looks very similar to my Yashicamat - 124. I had a similar issue with grease on the rear element, it must come from the shutter somehow, but a word of warning - the grease on mine had hardened and I couldn't adequately clean it off through the front. I still had to remove the rear element to clean it properly. It surprising that yours has no slots to unscrew it, perhaps some sort of friction device as described by Brcamera would help. As a last resort you might consider drilling two small holes either side in the retaining ring but it would he hard to do this without the drill slipping and causing damage. |
John_s
Tinkerer
Username: John_s
Post Number: 61
Registered: 07-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, October 20, 2011 - 08:07 am: |
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Yes you have just removed the front element and retaining ring, you need to get the rest of the front cell assembly out, it usually comes out in one piece. It looks very similar to my Yashicamat - 124. I had a similar issue with grease on the rear element, it must come from the shutter somehow, but a word of warning - the grease on mine had hardened and I couldn't adequately clean it off through the front. I still had to remove the rear element to clean it properly. It surprising that yours has no slots to unscrew it, perhaps some sort of friction device as described by Brcamera would help. As a last resort you might consider drilling two small holes either side in the retaining ring but it would he hard to do this without the drill slipping and causing damage. |
