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Thread: Pyrocat HD

  1. #1

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    Pyrocat HD

    On the Pyrocat HD website, under suggested developing times there is the following paragraph:

    Contrast Index
    These times, at the temperatures indicated, should give an approximate CI of .56 when measured with a densitometer in blue mode, appropriate for printing on graded silver papers of #2 contrast. For variable contrast silver papers be sure to increase development times by about 35%.


    Can someone explain why variable grade paper requires an extra 35% over a #2 paper, as printing through a #2 grade filter surely requires the same contrast of negative?

    Thanks
    Bruce

  2. #2
    jp's Avatar
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    Re: Pyrocat HD

    VC papers are sensitive to different colors (thus how contrast is controlled), so the color of the stain on pyro negatives affects contrast some. I don't increase development solely for the sake of VC paper, just use a VC filter.

  3. #3

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    Re: Pyrocat HD

    Quote Originally Posted by jp498 View Post
    VC papers are sensitive to different colors (thus how contrast is controlled), so the color of the stain on pyro negatives affects contrast some. I don't increase development solely for the sake of VC paper, just use a VC filter.
    Sorry if I mis-understood, but are you saying that if I use a VC filter, then the normal time is fine, and by giving the 35% extra, the stain acts as the VC filter and I just print straight onto VC paper with no filter?

    Bruce

  4. #4
    Bill Kostelec
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    Re: Pyrocat HD

    More like: The stain will make the neg print softer than your would expect, so the increased development will increase the native contrast of the film, thus bringing you back to a "normal" use of filters.

    Bill

  5. #5
    jp's Avatar
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    Re: Pyrocat HD

    Proper "as in traditional" exposure+development is something that prints on the desired paper at grade 2. The stain make it print softer. I'm not proper, so I just dial in a little magenta when using VC paper. Do whatever you want and start experimenting and taking photos.

  6. #6
    おせわに なります! Andrew O'Neill's Avatar
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    Re: Pyrocat HD

    My times are longer because: 1. I use a cold light head. 2. When printing with silver I use VC papers. 3. I use the same negatives for alt processes.
    You have to test to see what works for you.

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