Availability of 2 bath developers in Kodak's Technidol and XTOL

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I would love to have a two bath developer for Kodak Technidol or Kodak XTOL. Does anyone know where I can find these or does anyone have any useful ideas?

-- PJTaylor (pjt_123@hotmail.com), January 08, 2001


I'm curious why you think that a two bath version of either of these developers would have any advantage, since there are plenty of acutance and compensating formulae to choose from already.
Since both of these developers are proprietary, and the formulae haven't been released, then it's really an idle wish, unless you can persuade Kodak to reformulate them for you.

-- Pete Andrews (p.l.andrews@bham.ac.uk), January 09, 2001.

I have done tests in the past with Divided D76 and got some good results. A bit of a speed loss but the negs printed beautiful. Cheers

-- Scott Walton (scotlynn@shore.net), January 09, 2001.

Sorry PJ, I didn't mean that last response to sound dismissive, but it did strike me as a bit of a rhetorical question.
To take your points one at a time:
1)Sure, it's possible to analyse any chemical substance, but the facilities and expertise required to do so accurately are beyond most individuals means. Any organisation that reverse engineers a commercial product is unlikely to admit to it by making their findings public.
2)I think that, at one time, Kodak recommended the 2 bath Beutler developer for getting normal contrast with Technical pan. This may be origin of the 2 bath formula you were thinking of.
3)Splitting a developer into two baths, without modifying the formula, effectively gives you a different developer.
The developing agent available is limited to the amount that can be absorbed by the emulsion in the first bath, giving low maximum film density, and therefore turning the developer into a 'compensating' type. Because of this emulsion carry over, the characteristic of the developer will change with film type, and possibly format. The net result is the same as if the quantity of developing agent was only a fraction of the original formula, and the two bath version will give nothing like the same tonality or film speed of the original.

I hope this explains why I found it a rather curious request to begin with.

-- Pete Andrews (p.l.andrews@bham.ac.uk), January 09, 2001.

If a developer is available as a powder, the MSDS (material safety data sheets) should give you an impression of the formula. Or you may look for a patent of that developer.

You could use a two bath developer for Technical Pan, like Windisch (Brenzcatechine). Try something like this Bath A concentrate 10 g Brenzcatechine 2 g Na-sulfite 100 ml water

Bath B concentrate 10 g Na-hydroxid 100 ml water

Dilute A concentrate 1:14 4 mins Dilute B concentrate 1:24-1:29 around 2 mins



-- Wolfram Kollig (kollig@ipfdd.de), January 10, 2001.

Wolfram, the classic Windisch developer was only meant to be stored as a two part solution. The instructions state that parts A and B should be mixed a short time before use.
The formula I have is:
Part A:
Pyrocatechine ------12.5 gm
Sodium Sulphite ---- 80 gm
Water to ------- 1 litre
Part B:
Sodium Hydoxide ----- 60 gm
Water to ------- 600 cc.
The working solution is made by taking 25 cc of part A, 15 cc of part B, and making up to 1 litre with water.

-- Pete Andrews (p.l.andrews@bham.ac.uk), January 10, 2001.

Thanks Pete! Nevertheless I use the two bath brenzcatechine developer for TP.


-- Wolfram Kollig (kollig@ipfdd.de), January 10, 2001.

Also the MSDS in the US is only required to list components that are over 1%, are hazardous, and only approximate percentages have to be given. If you look at published developer formulas, very small seeming changes in the amount of one or more chemicals can make a big difference.

-- Terry Carraway (TCarraway@compuserve.com), January 10, 2001.

I've had good experience developing Tech Pan in Diafine. Develop in the "A" solution for the full 3+ minutes, then develop in the "b" solution for 45 seconds for condensers and 1 minute for diffusion illumination. Piece of cake.

-- Gene Crumpler (nikonguy@att.net), January 16, 2001.

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