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alexi
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, May 19, 2004 - 07:29 am: |
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Hi, I'm new to this forum... I have an F2 with focus problem? .....I was checking focus acuracy of another camera with a focusing screen with a split image at the film plane and dicided to check the F2 as I was at it...the F2 shows correct infinity focus ( the moon), 1 meter and 3meters through the mirror-pentaprism , but when I checked focus at 1 meter at the film plane with the focusing screen the split-image did not match the target image I had drawn on the wall( a straight line)....I was very careful to exactly place the camera's focal plane at one meter from the target by A) focusing with the camera and B)actually measuring the distance from the target to the focal plane with a measuring tape...I also checked that the camera was parallel to the wall....the image at the focal plane with the focusing screen did not match the line of the target. How can I adjust the flange to film plane distance of the F2...I am not familiar with the disassembly procedures of this camera and before I do this I would like to get some isntructions... I know with some screw mount rangefinders like Leica and the Russian rangefinders this can be rectified with the use of shims under the flange mount.....Is this also true for Nikon F2? or do I just have to adjust the screws that hold the mount in place? thanks ALexi |
rick oleson
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, May 19, 2004 - 09:50 am: |
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According to the figures I have, the correct distance is 46.50mm. However, changing this distance will change both the film plane register and the viewfinder together. You would then have to adjust the viewfinder to bring it back to match the film. |
Jan Dvorak
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, May 19, 2004 - 10:56 am: |
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Alexi, The most important test of all is a test with film. Is your 'film plane' infinity focus off as well? Tape measure tests at close distances are not always accurate... If your image on film is sharp when sharp on the screen, I would not worry about it. Jan |
David Nebenzahl
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, May 19, 2004 - 11:17 am: |
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What Jan said: if you get good in-focus pictures with this camera, forget about test setups involving 1-meter measurements, etc. Here's an idea: make yourself a focus test setup and photograph it. I used the method of lining up playing cards on a board, putting the cards at about a 45° angle to the board and spaced about a half-inch apart. (I used the backs of the cards, which had a pattern printed on them which was perfect for testing focus.) I placed this board so that the cards were parallel (more or less, doesn't matter that much) to the film plane. I then focused on a card in the center that I had drawn a line on, so I'd know in the resulting picture whether it was in focus or not. This test will tell you whether your camera+lens is focusing correctly, and it's as accurate a test as you'll ever need. |
Haig Hovaness
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, May 19, 2004 - 08:01 pm: |
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The distance scale markings on the lens are not always perfectly accurate. Take a picture of books on a shelf at a 45 degree angle from various close distances. If the book you are using as a focus target is OK, stop worrying. |
Haig Hovaness
Rating: N/A Votes: 0 (Vote!) | Posted on Wednesday, May 19, 2004 - 08:21 pm: |
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The distance scale markings on the lens are not always perfectly accurate. Take a picture of books on a shelf at a 45 degree angle from various close distances. If the book you are using as a focus target is OK, stop worrying. |
David Nebenzahl
Rating: N/A Votes: 0 (Vote!) | Posted on Thursday, May 20, 2004 - 01:32 am: |
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Haig's suggestion is an even simpler version of the one I made. (Just remember which book you focused on!) And above all, be sure to stop worrying if the pictures come out properly focused. |