Dixactol - solution A?

Discussion in 'B&W: Film, Paper, Chemistry' started by Usagi, Apr 15, 2009.

  1. Usagi

    Usagi Member

    Apr 17, 2007
    Turku, Finla
    Multi Format

    Does anyone know what is the exact function of solution A of Dixactol developer? If I change the amount of solution A from the recommended (1 ml of A + 7 ml of B to 300 ml of water), what effects should I expect?

    I run to this when I accidentally mixed 3 times too much of solution A to developer (ie: 6ml + 14ml + 600ml).
    To my big suprise the negatives seems to be fine. For an eye, they look a bit thin and contrasty. Probably the stain is also stronger than normally.

    I have not yet printed them, but they scans really easily. Perhaps one of the easiest negatives to scan I have ever had!

    Duh, the world of B&W chemichals is weird :confused:
  2. sanking

    sanking Member

    Mar 26, 2003
    Large Format
    Dixactol is a two part pyro staining solution. The formula is proprietary, but appears to be based on catechol rather than pyrogallol. I would hazard a guess that Part A contains catechol + a preservative, probably sodium bisulfite or sodium metabisulfite. Part B is the alkaline accelerator, and could be a number of things, but is most likely either sodium carbonate or sodium hydroxide.

    If the required dilution was 1ml A + 7ml B + 300ml of water, and you used 6ml A + 14ml B + 600ml water you basically would have a slightly more energetic working solution. If your negatives came out thin, it would have been from under-exposure, not from the dilution of the developer.

    Hope this helps.