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  1. #11

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    Does the problem exist with multiple lenses, or just one. I once owned a 55mm lens that was simply soft for unknown reasons. I replaced it with a different one that is sharp.

  2. #12
    PeterB's Avatar
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    I only own the 80mm lens. The image is VERY sharp once it is focused. The problem is that the when the viewing screen is in focus, the image isn't in focus on the film plane.

  3. #13

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    I had the same problem you describe. For some reason,the magnifier in the waist-level finder finder did not focus properly on the ground glass. I had to do some surgery to bring the two into alignment.
    Very strange,because the finder was in excellent shape,and not damaged in any way.
    My dual-magnification chimney finder needed a similar adjustment to bring the swing-in second element into alignment.

  4. #14
    PeterB's Avatar
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    Thanks smudger. Your description of the problem is the first I have encountered in any forum (and I've been combing them for solutions for weeks now) and I'm sceptical about the explanation. It doesn't make sense that if the original magnifier in the waist level finder (WLF) is not positioned correctly that it would prevent one from focusing. Sure the image viewed through the WLF won't be sharp, but at least when it is as sharp as it can get then that is the right point. I can't see a need to add a second lens in the WLF. Please try and convince me otherwise.

  5. #15
    MattKing's Avatar
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    Has someone installed an accessory diopter correction lens in your WLF magnifier?
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  6. #16
    PeterB's Avatar
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    Quote Originally Posted by MattKing View Post
    Has someone installed an accessory diopter correction lens in your WLF magnifier?
    Not AFAIK. I will check tonight though, BUT even if they had how is that going to make a difference to the optimal point of focus ?? I have glasses that I sometimes wear to sharpen things in the distance. The problem I see with my C330f's mismatched focus is identical (to within limits of repeatability) whether I put my glasses on or not. Therefore if the WLF lens' diopter isn't the original default, and I swapped the default back in, this is identical to me focussing with my glasses on or off.

    Sure things will come to a sharper focus with my glasses on (or with the default WLF diopter viewed by somebody who doesn't use glasses), but this shouldn't change the actual optimal position of the main lens assembly on the track/rail.

    Matt, your suggestion is based on the same false premise as smudger which I attempted to counter in my above reply to him.

  7. #17
    MattKing's Avatar
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    Peter:

    I agree that an incorrect diopter would merely make it more difficult to determine visual focus. I guess I was responding more to the OP's description of his camera.
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  8. #18
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    Quote Originally Posted by MattKing View Post
    Peter:

    I agree that an incorrect diopter would merely make it more difficult to determine visual focus. I guess I was responding more to the OP's description of his camera.
    Yes, your reply makes sense now Matt. I think I might need to purchase the camera's service manual to determine the cause of my focus discrepancies.

  9. #19

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    Depending on the screen, the sharpest point doesn't look that sharp. Mine is C3 with old fashioned ground glass, which is easy to reach the optimum focus point, but the image is rather dark and coarse.

  10. #20
    PeterB's Avatar
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    Quote Originally Posted by Ryuji View Post
    Depending on the screen, the sharpest point doesn't look that sharp. Mine is C3 with old fashioned ground glass, which is easy to reach the optimum focus point, but the image is rather dark and coarse.
    I totally agree Ryujii. However even though the image on my viewing screen isn't razor sharp, it is very easy to determine the point that it is the sharpest it can be (as one turns the focus knob). That point by definition is when the object is in focus.

    My problem isn't that the image in the viewing screen (via the viewing lens) isn't sufficiently sharp. My problem is when that image is as sharp as it gets, the corresponding image in the film plane (via the taking lens) isn't as sharp as it can get. I have to move the main lens assembly back and forth by about 0.6mm (focus knob turns about 2mm circumferentially) as I switch between looking at the film plane and the viewing screen to ensure each is at its sharpest.
    I'm impressed that TLR camera manufacturers were able to manufacture their cameras to sufficiently high precision to ensure appropriate lens and image alignments in the first place.

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