chemical quantity question

Discussion in 'Color: Film, Paper, and Chemistry' started by nlochner, Aug 20, 2006.

  1. nlochner

    nlochner Member

    Messages:
    54
    Joined:
    Jun 17, 2006
    Location:
    Michigan
    Shooter:
    Multi Format
    Hello, i just bought a "colour by beseler" RA-4 11x14 printing drum, and i was wondering how much chemical i should put in it every time. My 8x10 drums require roughly 1.5 oz chemical.


    Thanks very much

    nlochner
     
  2. donbga

    donbga Member

    Messages:
    2,084
    Joined:
    Nov 7, 2003
    Shooter:
    Large Format Pan
    3 ozs.
     
  3. nlochner

    nlochner Member

    Messages:
    54
    Joined:
    Jun 17, 2006
    Location:
    Michigan
    Shooter:
    Multi Format
    I just printed a photograph, and it's perfect, so 3 oz. worked well.

    Thanks, alot

    nlochner
     
  4. Mike Wilde

    Mike Wilde Member

    Messages:
    2,936
    Joined:
    Aug 10, 2006
    Location:
    Misissauaga
    Shooter:
    Multi Format
    Not all chemicals are treated equally in RA-4

    Your question pertains to how much to put in the tank.

    There is also the issue of how much chemistry the print actually consumes.

    If you buy your chemistry in a kit it may not matter, but if the individual dev, stop , and blix are bought separately then there is the opportunity for economies.

    Use 3 oz developer, fresh every time.

    Use fresh stop every time . You may be able to make your own stop from
    diluting conventional B&W stop bath stock solution. I make mine using 10ml of 80%+ glacial acetic acid per litre.

    Use 3 oz of fresh blix for the first print. Save it in a jug. For the second print add 2 oz of fresh blix, and the balance of re-used blix.

    The major cost of the process is the ferric ammonium EDTA in the blix, and it is not all consumed, but the 80ml is needed to wet the print.