thiocarbamide toninggreenspun.com : LUSENET : B&W Photo - Printing & Finishing : One Thread
I've been attempting to sepia tone fiber-based prints using a thiocarbamide formula suggested by Eddie Ephraums in his book "Creative Elements." It consists of a mixture of thiocarbamide and sodium hydroxide in varying proportions, depending on the desired effect. I have yet to see even the slightest amount of toning, no matter what the mixture, temperature, time, or paper type (Forte Polygrade, Ilford MG IV, Kodak Polyfiber, various RCs). I'm at a loss. Does the emulsion makeup (bromide vs. chlorobromide) make a difference? Type of fixer? Anyone out there have success with this toner?
-- Greg Nelson (firstname.lastname@example.org), January 15, 2000
I have never used a thiocarbamide formula for toning, so I may be way off base here. But my experience with toning causes me to ask the following two questions, which may help you. Are you leaving the prints in the toner long enough? Some toners, specifically Kodak Brown toner (1:10), requires a considerable amount of time to show results. For the full effect with Ilford Warm tone fiber paper in brown toner, I tone for a full twenty minutes. Iford Warm tone fiber in Selenium (1:10) requires about eight minutes before you will see appreciable changes. My second question has to do with your choice of papers. Cold tone papers will show little or no change as a result of toner. I would suggest using Ilford Warm tone fiber, or Forte Polywarmtone fiber paper for your experiments with the thiocarbamide toner. Personally, I prefer the Ilford Warm tone fiber, as the Forte Polywarmtone fiber is a bit too receptive to toner, especially selenium, for my tastes. Good luck, Tom Schumacher
-- Tom Schumacher (email@example.com), January 15, 2000.
Greg..... I get huge results with the thiocarbamide toning from rich chocolate browns to yellow browns depending on the ratios of thio to hydroxide with Agfa Multigrades and Ilford multigrade Resin Coated Papers. I can only suggest something wrong with your chemistry. Cheers David Strachan.
-- David Strachan (firstname.lastname@example.org), January 15, 2000.
The effect is fast and very obvious. If you are getting no toning, something is very wrong.
You are bleaching first, aren't you?
Take a properly developed, fixed and washed print. Bleach it in ferricyanide/bromide until the blacks turn into a very light brown, or even dissappear entirely. Depending on the strength of the bleach, this will take about 2 minutes. If that doesn't work, there is something wrong with the bleach. (When you have the process working, you might prefer a very small amount of bleaching. But for a test, try a heavy bleach first.)
Wash the print thoroughly. Put it in the toner. In a few seconds, the image should reappear, in a yellowish-brown to purplish-brown colour, depending on the thiocarbamide/hydroxide ratio. After one minute, there should be no more colour change. If that doesn't work, there is something wrong with the toner.
-- Alan Gibson (Alan.Gibson@technologist.com), January 15, 2000.
the only thing i can think you might be doing wrong is using dead toner. if i remember correctly from using some formulary toner some time ago, thiourea/thiocarbamide toner is two solutions which you mix immediately prior to toning. the toning solution is self destructive chemically, so you have to use it within a short time of mixing or it dies. did you by chance misunderstand this in the ephraums book and mix the final solution?
-- brad daly (email@example.com), January 16, 2000.
In my experience, the mixed toner keeps well, but the bleach doesn't, because it is very sensitive to light. I always make up fresh bleach, from dry chemicals, as I need it.
-- Alan Gibson (Alan.Gibson@technologist.com), January 17, 2000.
I also use the formula from Eddie Ephraums book and get excellant results. Never had a single problem. Follow it to the letter.
-- Gaz Rowlands (firstname.lastname@example.org), January 18, 2000.
Thiocarbamide/sodium hydroxide is a redeveloper. You have to bleach first. Use Kodak Sepia Toner bleach.
-- Peter Hughes (email@example.com), January 31, 2000.