Re: A little gum test

Hi Mark, Less contrast with the saturated solution was postulated....so I'thought I'd give it a whirl. I have been getting rather flat prints so this is good news. The results (to me) show some of the reason why I've been having some trouble with this technique - obviously too much amm.di. I think the reason why the tones are better is that mostly I've just been overexposing with the amm. di. at the more concentrated level...
  ----- Original Message -----
  From: Ender100@aol.com
  To: alt-photo-process-l@sask.usask.ca
  Sent: Monday, December 15, 2003 10:41 AM
  Subject: Re: A little gum test

  Kate and others,

  I am trying to remember ealier posts, wasn't there a post that stated that a more diluted silution of dichromate gave more contrast and thus a lower range of tones?

  Pardon my bad memory.

  Mark Nelson
  In a message dated 12/14/03 3:28:41 PM, kateb@paradise.net.nz writes:

    Hi all, I have just done a little series of tests to look at the difference between saturated amm. di. solution and the same solution at 50% strength (which I imagine is 15% - but what would I know, I'm no chemist). The results were very obvious - the half-strength solution gave a much wider range of tones than the full strength with both the Winsor and Newton bottled gum and the "generic"gum I mix myself from powder ("borrowed" from the printmaking dept). I also threw in a bottled "gum" used by school kids for generations - this gave better results with the full strength solution. Interesting! All on Arches Aquarelle paper, tray sized with gelatine+ formaldehyde. The "gum"might be similar to Gloy but I have no idea what its constituents are - it tastes quite organic. Strange to say, I never tasted it when I was a child - how I am deteriorating!

    Kate Mahoney
Received on Mon Dec 15 00:20:58 2003