warmer slower paper formulation question

Discussion in 'Silver Gelatin Based Emulsion Making & Coating' started by dpurdy, May 5, 2009.

  1. dpurdy

    dpurdy Subscriber

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    This is a question about a commercially produced paper that has been reformulated and undergone significant change. I am curious if I list the changes if perhaps Ron or someone else can make an educated guess. I realize it is like shaking a can to check it's contents.

    Oriental VC-FB warmtone has been reformulated and I have tested it side by side for a couple days and these are the differences I find.
    the New paper is:

    Much warmer even in the unexposed border though the paper stock looks the same on the back.

    Much slower to print, about half the speed.

    Less flexible color due to developer changes. (I used Amidol, A130 and D54) It made no difference in the tonal color.

    Much flatter to print on a VC head. Needs very high contrast setting.

    Seems to need 3 minutes development to achieve Dmax compared to 2 minutes on the old.

    New paper tones very quickly in Selenium. 1-9 dilution yank it out in about 30 seconds. Already going very red in color.

    New paper bleaches very quickly in Potas. Ferricyanide. Have to use it really dilute.

    Would these symptoms be typical of something?

    thanks
    Dennis
     
  2. Photo Engineer

    Photo Engineer Subscriber

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    Sounds like a tint was added to the baryta coating on the front as well as a change to the halide balance in the coating. The amount of sulfur may have been reduced as well. It is hard to tell, as you say. There may be more than one answer to the changes you see.

    PE