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  1. #1

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    Contact Proof Printing with Enlarger

    I'm doing contact proof printing with my 4x5 enlarger. Some questions:
    1. Do you focus the light on the proofer, then remove the negative? Or focus is not required?
    2. What lens do you normally use? short or long? With short focus length, the lens is closer, but light spreads out. Long focus length lens tends to be stronger.
    3. What aperture and exposure time do you recommend? Small aperture and longer exposure time for sharper images?
    4. Since this is using enlarger, I figure enlarger paper is needed.

    Thx.

  2. #2
    cliveh's Avatar
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    I would make a rectangle of light a bit larger than your proof printer, focus on the baseboard, normal lens, stop down about two stops and make test strips. You could try about 6 seconds, but you need to test.

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

  3. #3

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    When I used 50mm lens, I had to open the lens to F8 and 14 sec. It was faster when I used the 80mm lens. Of course, there are other variables.

  4. #4

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    Use the same focal length you use for enlarging those negatives
    Set the enlarger at the height it would be for your usual print from whatever size neg. I use the height needed for an 8x10
    I have the heights marked on my column for each format I use.
    Focus the lens using the edge of an empty carrier, expose with a carrier in place.
    Use the same stop you normally use for printing, for me that's always 2 stops down from the lens's maximum.
    Use the minimum exposure to get a maximum black through the film rebate
    Yes, you use enlarging paper.

    If you set things up this way then you will know how much exposure the negative will need when you enlarge it. If you use the same grade or filtration for all proofs then you can be in a better position to judge what grade you'll want for your initial test print.
    Basically this is the procedure Fred Picker calls making a "proper proof".

  5. #5
    jp498's Avatar
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    I've done pretty close to this, but purposely de-focus. Why would I want a sharp shape of light to hit the contact printing frame? It's all about even exposure.

    I use my Chromega B enlarger (6x6) with a 80mm lens for contact prints and medium/small format enlarging. I set the height as described, then turn it 1/4 turn out of focus. I have penciled on my baseboard where to put the contact printing sandwich.

  6. #6

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    This makes sense. It takes out a lot of the variables and make this part of the enlarging process....

  7. #7

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    sharp shape of light

    My head hurts. A sharp shape of light and uneven exposure. Do you de-focus when you make a photo print so you won't get uneven exposure? Hummm. Well, WHATEVER WORKS FOR YOU. I'm going to crack a photo book and read up on "circles of confusion." I'm confoosed.

  8. #8
    jp498's Avatar
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    If there is absolutely nothing in the film carrier, there should be no need to focus or defocus.
    Except moving the lens in and out focusing does affect exposure (aka bellows factor), so some consistency is good.
    If there are any reflections (or stray hairs/lint or whatever) with regard to the film carrier, it seems having it out of focus would be preferable to me. My film carrier is plain unpainted aluminum. Having no film carrier would create gaps beaming light out all over the darkroom.

  9. #9
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    If you plan to do a lot of contact printing, you can also process a piece of unexposed film. You then use the neg to determine a standard print time. You do this by doing a series of exposures with the blank neg on your print. You pick the exposure time where you start to get total black on the print. Basically, you want to expose just enough to achieve your Dmax. Make some notes on the height of the enlarger, exposure time and what f stop you used. This will make contacting more efficient if you plan to do a bunch.
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
    Aaron Chang

  10. #10
    ic-racer's Avatar
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    You will want to stopdown about 3 stops to improve evenness. Longer lens is better. You want to focus the light, otherwise there can be too much light falloff. Also, if using a condenser enlarger, you certainly need to focus the lens, otherwise the lighting will be uneven.

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