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Tom_b
Tinkerer
Username: Tom_b
Post Number: 3
Registered: 08-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 01, 2007 - 12:38 pm: | 
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I sent my Retina IIa off for a CLA, thinking I would make it a point to use it more. Messing with it when it came back, I noticed that pictures taken at f8 ,f11 or f16 are pretty good. At the other end (under identical conditions, same roll of film), anything at f4, f2.8 or f2 is completely out of focus. Not just a different depth of field - out of focus all the way to the horizon! And, obviously, in order to take the picture at a huge opening, the speed was at the high end (1/500), so it was not camera shake.
Before I wag my electronic finger at the guy who "tuned up" my camera, I'd like to get an idea why this would happen.
Thanks |
Charlie
Tinkerer
Username: Charlie
Post Number: 64
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 01, 2007 - 12:48 pm: |
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Are you using the scale or the rangefinder? |
Tom_b
Tinkerer
Username: Tom_b
Post Number: 4
Registered: 08-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 01, 2007 - 02:02 pm: |
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The rangefinder. That was adjusted as part of the "tune up" - could it be so far off that I have NO depth of field at the larger apertures ? |
Jan
Tinkerer
Username: Jan
Post Number: 31
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, May 01, 2007 - 07:07 pm: |
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Tom,
is the RF aligned correctly at infinity? It sound to me more like the lens assembly is not sitting where it should be or, was not put together properly after disassembly. Obviously, what is happening is that the depth of field is taking care of the misalignment when the lens is closed down.
If you have a small piece of ground glass that would fit on the film rails, you can check your infinity focus with the camera on tripod, shutter on 'B' and full f-stop. If you do not have ground glass, try wax paper with the matt side to the lens. You should focus on the ground glass and than check the rangefinder image for any discrepancy at different distances, starting at infinity and going down. Use tape measure at distances closer than 15' (5 meters) to determine what is out of whack - lens assembly or the RF.
It is quite a straightforward process of elimination to find out where the problem lies - either improper lens to film distance, or inaccurate rangefinder.
Good luck,
Jan |
Charlie
Tinkerer
Username: Charlie
Post Number: 65
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 02, 2007 - 06:01 am: |
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If you Google "Chris's camera pages" Chris Sherlock has a page on how to adjust a Retina IIa rangefinder if you need to do it. |
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