Durst M670VC Paper Contrast Settings

Discussion in 'Darkroom Equipment' started by Obtong, Jul 20, 2010.

  1. Obtong

    Obtong Member

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    Hi all,

    I'm looking to buy a Durst M670 Variable Contrast enlarger. With one dial I can apparently set different contrast settings and keep the exposure constant if changing paper/contrast grades. Does anyone know if the numbers on the Durst M670VC filter head dial match Ilford MG IV paper grades?

    Thanks,
    ~Dom
     
  2. Ian Grant

    Ian Grant Subscriber

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  3. monodave

    monodave Member

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    They are also on the leaflet in every box of Ilford paper. Dave
     
  4. Obtong

    Obtong Member

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    Thanks for the responses. The Ilford inserts show filtration for Durst Color enlargers (such as the M605C) where you dial in a combination of Yellow and Magenta to get the correct contrast.

    The Durst M605VC (Variable Contrast) enlarger has a single dial to dial in the contrast filter. I am trying to find out if the numbers on this single dial correspond directly to Ilford MG papers. The Ilford Recommendations Guide does not list the M605VC as a unit that has been designed for use with Ilford MG papers.

    I already have the M605C and have found setting two different dials each time I need a paper grade change somewhat cumbersom. I am hoping that the single dial M605VC might be easier to use.

    ~Dom
     
  5. ic-racer

    ic-racer Member

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    Easy to test with a 21 step wedge.

    If the middle gray stays the same across all contrast settings for the same exposure, that is well suited to Ilford MG without exposure correction (just what you want!)

    In terms of the number on the dial on the enlarger head, you can count the number of grays and throw out the 'almost white' and 'almost black' bands. Multiply by 15 to get the ISO (R) number and compare to a chart of ISO (R) vs Grade Number.
     
  6. Ian Grant

    Ian Grant Subscriber

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    Apologies missed the VC head bit.

    It's not really that important if the nominal Grades do or don't line up identically. What's more important is the even spacing and what extremes it will go to.

    There's variation in enlarger lamps, lenses etc, so no two different enlargers will necessarily give identical VC graded, and papers vary with age and between manufacturers.

    Yes it will be slightly easer to use, as long as it reaches at least Gd 0 and close to Gd 5 at the two ends it'll have plenty of flexibility in the mid range which is where 95% of your negatives should print.

    Ian
     
  7. shorton787

    shorton787 Member

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    Dom -
    You still looking?
    Steve