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Esfandiar
Rating: N/A Votes: 0 (Vote!) | Posted on Tuesday, April 05, 2005 - 09:45 am: |
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Hi, I have just received a Moskva 5 and the rangefinder apparently does not work. Here is the problem: the image in the round rangefinder window is completely sharp, regardless of how much I turn the focussing ring. I have checked the following things and nothing has changed: 1. the arm with the round rangefinder prisms is in the up position (but it makes no difference whether this is the case or not), 2. I removed the to cap and cleaned the lenses and prism, the image is clearer, but still no "ghost image" 3. the round focusing prisms turn in opposite directions when you turn the focusing ring or the focusing wheel. It looks as if I get the image from the round window that is not aligned with the round focusing prisms only. Thank you for your suggestions. Esfandiar |
rick oleson
Rating: N/A Votes: 0 (Vote!) | Posted on Tuesday, April 05, 2005 - 10:56 am: |
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while looking through the rangefinder, hold a finger in front of the prism window on the extended arm. do you see your finger through the eyepiece? if not, you have lost the secondary rangefinder image and the finder unit on the body will need to be repaired. |
rick oleson
Rating: N/A Votes: 0 (Vote!) | Posted on Tuesday, April 05, 2005 - 10:59 am: |
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oops, i think i was on the wrong side.... try the above with your finger in front of the other window too. : ) = |
Esfandiar
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, April 06, 2005 - 02:43 am: |
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Rick, Thanks for your advice. Here is the result of the test: 1. If I hold a finger in front of the prism window on the extended arm (or in front of the window on the body aligned with the arm) I can see nothing through the eyepiece, 2. If I hold my finger in front of the other window, then I can see my finger through the eyepiece. I really hope the problem is with the unit in the body rather than in the arm, because the body looks simpler than the arm. An additional detail that may help is that I simply cleaned the round prisms on the arm without disassembling them and can still see fingerprints on them. I think that the finger prints are left inside the round prisms and they must have been opened at some point. Thank you again for any idea. Esfandiar |
rick oleson
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, April 06, 2005 - 06:37 am: |
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I haven't had one of these apart, I don't know if it has mirrors or prisms in it - but it sounds like something has come unglued inside. And the fingerprints definitely mean it's been tinkered with, whick means that it could be way out of adjustment when you do get the basic functions back in order. |
Winfried
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, April 06, 2005 - 06:52 am: |
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The Moskva5 has a long prism inside the viewfinder cover. One surface is semi-silvered. Maybe the silvering has gone, so you don't see a double image. From my experience with russian cameras I think it is even possible the prism is missing completely. To remove the top cover, unscrew the round windows and remove the top part of the advance button (maybe there is a holding screw under it), and lift the cover. Maybe I still have a prism somewhere, if you need it you can have it. Concerning the finger prints inside the rotating prism, this happens very easily when taking them apart. If you disassemble the rotating prisms mark the position of all the gears. It is possible to readjust the prisms even if their initial position is totally wrong (in this case the double image moves vertically, or sometimes even in the opposite direction as intended) but it takes patience. |
Winfried
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, April 06, 2005 - 06:54 am: |
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I just read your first post, the prism seems to be in place... so my best guess is that the semi-silvered surface is damaged. In this case you will need a replacement. It is normal that the two rotating prims rotate in opposite directions. However, I have always seen a double image (even if in completely wrong orientation) at certain focussing distances. |
Esfandiar
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, April 06, 2005 - 11:17 am: |
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Thank you for your comments. I confirm that I checked inside the body and there is a long glass prism there. I will open it again and check the silvering. Judging from the dust inside, I have the impression that nobody had been there for a few decades. So is it possible that the silvering goes away by itself? Would it be possible to somehow resilver the prism instead of replacing it? I have read in another context that you can repair a damaged mirror on an SLR with aluminum foil... Esfandiar |
Esfandiar
Rating: N/A Votes: 0 (Vote!) | Posted on Thursday, April 07, 2005 - 03:48 am: |
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Hi, I looked at the long glass prism inside the body again. It does not look beat up at all; that is why I think if there is a defect there, it must be a production defect. Besides, the silvering seems to be inside the prism element and it should not be easy to reach the part to resilver. I guess the only solution is a spare part... While I was at it I tested the prism. If you look at the square end (the part close to the eyepiece), you see the image at the window not aligned with the prism arm. If you look at the sharp end (opposite the window that is not aligned with the prism arm), you see the image at the window aligned with the prism arm. So I think that the problem is that this latter image somehow does not get reflected back to the eyepiece. (I hope this makes sense). |
Winfried
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, April 08, 2005 - 12:00 am: |
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I just checked the spare prism (it is still mounted on a Moskva5 junk body I was planning to trash soon). When looking into the eyepiece opening of the naked prism (i.e. without viewfinder cap, rangefinder windows and the rangefinder arm not in place) you should see a clearly separated double image of objects which are a few feet (1 or 2 meters) away. If this is not the case I think the silvering in the prism has gone. I am going to answer your private request soon. |
Esfandiar
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, April 08, 2005 - 02:16 am: |
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Winfried, Sadly, the image is all too sharp. It looks as if the silvering is gone or the angle of the element inside is messed up. Thanks for having checked this for me. |
Winfried
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, April 08, 2005 - 07:56 am: |
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What do you mean by 'all too sharp'? Do you see one single image of close objects? |
Esfandiar
Rating: N/A Votes: 0 (Vote!) | Posted on Friday, April 08, 2005 - 09:27 am: |
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Yes, one single image. |