Defender / DuPont 6T Toning System, questions

[Marco Buonocore]

In another thread, a member mentioned the use of Defender / Dupont's thiocarbamide based toner.

I've used the formula in Anchell's Darkroom Cookbook, 2nd edition, p 237. It's the same formula as Tim Rudman has in his book on Toning (p32).

I noticed in the following link:

http://silvergrain.org/Photo-Tech/toners.html

that in Toner #3 (T3), it calls for 44g of Thiourea in 1L of water - while in the other sources it calls for 3g in 1L. Quite a difference!

Having done 3 sessions with the toner, using B1 & B2 (no nitric acid on hand for B3), and having made T1, T2, and T3, I am exited by the possibilities.

My goal is to recreate the effect I get with Kodak's Sepia toner. I'm in a shared darkroom, so odourless is a big deal. The B2 & T3 combo has been quite promising on Ilford Warmtone. I've been selenium toning first to get a nice split.

I have a couple of questions:

1: why does the potassium iodide & potassium ferricyanide bleach (B2) turn the print base blue? I've never seen anything like it. Should I wash the blue out before redeveloping, or is that unnecessary?

2: How long do I redevelop for? With Kodak's Sepia, it's all done and dusted in less than a minute. With the T3 formula (the one from the darkroom cookbook), it's hard to tell when it's complete. I was waiting up to 4-5 minutes.

3. With question #2 in mind, is there any way I can speed the redevelopment up making a higher concentrated formula? ie: 9g thiocarbamide + 144g Potasssium Carbonate + 1000ml water. Will this work?

I'd also be interested to know if people think it's worth making the B3 Bleach; I'm aiming to make selenium / sepia splits, with as golden a highlight as I can manager.

Thanks in advance!

 

[Rich Ullsmith]

I dissolve 100g of toner into 1L of water to make stock solution. For working solution, it's anywhere from 10 to 50 mils of stock into 1L of water. Your sources that say 3g into 1L would produce a mid-brown effect, so that makes sense to me. The 44g in 1L does not, unless that is for a stock solution.

If you want yellow/yellow-brown highlights, use a little toner and lots of activator. It can take a few minutes to tone to completion.

 

[Marco Buonocore]

Thanks Rich,

I'll try to to use less thiocarbimide and more potassium carbonate, and see how the colours change. I was super impressed with how an Ilford Multigrade print looked last night. Couldn't believe the colour shift!

Does anyone know the capicity for a toning bath like this? Or how to predict how long it takes to 'tone to completion'? Is there any harm it letting a print sit in the toning bath for 5 minutes to ensure that a print is fully toned?

Alot of questions, I know!