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  1. #1

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    JOBO LPL 7451 color module used as a B/W module?

    Hi all.

    I just bought a JOBO 7451 with a color module.

    Do you think it is possible to use this color module as a B/W module for monochrome prints?

    I would think you would need some kind of reference chart or converter chart to do it.

    It is a really nice enlarger, and I hope to be able to use it.

    Any ideas?

    Thank you.

    Erik

  2. #2
    Sirius Glass's Avatar
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    I use my Jobo tanks for both black & white and color processing.
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  3. #3

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    I have the MXL 670 with color head. Not sure of the differences between the 2 enlargers but you can use a color head for contrast control. My negatives are very consistent. I found it easy to just dial in magenta to increase contrast. My normal filtration is between 2 1/2 and 3 1/2, a rather narrow range. The exposure times will change slightly (under 10%). To balance exposure time between contrast grades dial in yellow with magenta in different ratios per the photo paper directions. This adds density and increases the exposure time which you may not like. Remove the red filter from the under the lens red filter assemble. Just place flat contrast filters where the red filter was.
    RJ

  4. #4
    Sirius Glass's Avatar
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    I use a color head for black & white printing.
    Warning!! Handling a Hasselblad can be harmful to your financial well being!

    Nothing beats a great piece of glass!

    I leave the digital work for the urologists and proctologists.

  5. #5

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    No reason not to use a color head when doing BW. If you use Multigrade paper its the easiest thing in the world. One of the super cool things about this LPL (or Jobo) color head is that it is stepless, which means there is almost no change in time when you apply the filters. Increase magenta for higher contrast, increase yellow for lower contrast, or use both to create a more fine tuning.

    Use both separately to create a split print, use the yellow to activate the low contrast layer of your variable contrast paper, then use the magenta to activate the high contrast layer, creating a larger dinamic range on the paper the would normally be possible with just a single pass.
    CatLABS of JP
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    www.catlabs.info | https://www.facebook.com/CatLABS.of.JP | www.jobo-usa.com

  6. #6
    ic-racer's Avatar
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    Quote Originally Posted by Photonaut View Post

    I would think you would need some kind of reference chart or converter chart to do it.
    http://www.ilfordphoto.com/Webfiles/...8932591755.pdf

  7. #7

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    Thank you all for your response. Great information!

    E



 

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