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  1. #21

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    Quote Originally Posted by ic-racer View Post
    I was actually comparing the two methods.

    Since projection prints are much easier to make in my darkroom, I wanted to compare some 1:1s to to contact prints. I'm not going to comment on which looks better at this time. I know my Rodenstock 300mm lens field flatness deteriorates at 1:1, thus requiring f16, so the tests have not been 'fair.' A process lens would be better, but I don't have one.
    Great post. Just the other day I stumbled upon the two focal pt. phenomenon when setting up for making prints at 1:1. Another aspect of 1:1 printing that I'm finding especially vexing is focusing; grain appears sharp under grain focuser, but soft in print. Any ideas?

  2. #22
    richard ide's Avatar
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    "Great post. Just the other day I stumbled upon the two focal pt. phenomenon when setting up for making prints at 1:1. Another aspect of 1:1 printing that I'm finding especially vexing is focusing; grain appears sharp under grain focuser, but soft in print. Any ideas?"

    Possible reasons could include: chromatic aberrations, haze on lens surfaces causing flare, enlargement factor outside recommended range, uncoated lens etc. etc.

    What lens are you using and is it coated?

    Another possible reason might be your grain focusser being off.
    Richard

    Why are there no speaker jacks on a stereo camera?

  3. #23

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    Cool enlarger trick

    Grain sharp in focusser, not on print... I think there is unjustified faith that all grain focussers are spot on. I have several grain focussers, including long and short Patersons, a Peak 111, and a Focoblitz. I focussed on the grain at high magnification with each and printed a small section from the middle of the negative. Only the Focoblitz gave sharp grain in the print. So the others are very slightly "out". You could try focussing a little above and below the point that your focusser says is sharp, to see if your grain gets any sharper in the print. Unfortunately there is no way to calibrate or adjust any grain focusser that I have seen.

  4. #24
    glbeas's Avatar
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    Quote Originally Posted by youngrichard View Post
    Unfortunately there is no way to calibrate or adjust any grain focusser that I have seen.
    You can correct in one direction by pasting sheets of paper to the bottom of the focusser. The other way is a bit problematic, most folks wouldn't want to sand material off the bottom of thier scope to correct it.
    Gary Beasley

  5. #25
    ZorkiKat's Avatar
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    Quote Originally Posted by glbeas View Post
    You can correct in one direction by pasting sheets of paper to the bottom of the focusser. The other way is a bit problematic, most folks wouldn't want to sand material off the bottom of thier scope to correct it.

    In some grain magnifiers, the mirror can be moved up or down with a simple set screw. The aerial image therefore is moved as well. The key is to get the mirror surface (if front-surfaced mirror is used) to enlarger lens distance exactly the same as the mirror surface to magnifier base/paper surface distance. Just like the reflex mirrors of slr cameras.
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  6. #26
    gainer's Avatar
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    The initial magnification is less than 1. The image is smaller than the negative. As the distance from the lens to the easel approaches the focal length of the lens, the size of the image approaches infinitesimal compared to the negative and the bellows draw approaches infinity.
    Gadget Gainer

  7. #27
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    OOPS! Sorry, I didn't look to see that the puzzle had been solved.
    Gadget Gainer

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