Pyrogallol Paper Developer

[Donald Miller]

For those who may be interested in trying a Pyrogallol paper developer, I am posting the latest formula that I have been working with.

43 gm Sodium Sulfite

.3 gm Phenidone

10 gm Catechol

5 gm Pyrogallol

3.5 gm Potassium Bromide

50 gm Sodium Carbonate

Water to make 1 liter

Dilute 1-1 to make 2 liters of use solution

The Phenidone is most easily dissolved in alcohol. It is strongly advised to use eye, respiratory and hand protection when working with Pyrogallol just as in any pyro formulation.

I would appreciate feedback if you decide to use this formulation

[Doremus Scudder]

Don:

Given the short working life of pyro film developers, I find it hard to imagine that a pyro-based print developer would live through even one print from start to finish the way I work! Do you have any info on tray life of this formula as well as print tone, etc? (I probably won't switch my print developers any time soon; just curious.)

Regards

[Jonathan Borden]

What is the advantage of this over, say, an Amidol developer?

[lee\c]

I would think the main advantage of Don's pyro developer is cost and it is more warmtone than Amidol. I have never used the developer yet but have seen a couple of prints and they look mighty good.

leec

[Donald Miller]

Doremus,

This formulation is quite a bit different then a pyro film developer, for example. I find that it loses gas at about four hours in a tray. The print tone is neutral in my tests with Azo, Seagull VCFB, and JandC Polywarmtone (the polywarmtone will not go neutral but it will not warmer either).

Jonathan,

The advantage to Amidol is primarily one of cost per liter of use solution. My calculations place the cost of this pyro formulation at $1.17 per liter of use solution. The comparable cost of the MAS Amidol formula is $4.16 per liter of use solution. I will mention that the MAS Amidol formula is an excellent developer. I have used it for several years.

This is a very active formula. Emergence times are in the 14 second range with conventional enlarging papers compared to 45 seconds with Dektol. Emergence time is the same to slightly shorter then MAS Amidol with Azo. Dmax with Seagull VCFB is 2.07 when measured with my Xrite 310TR. My experience indicates that I gain about a stop in effective paper speed with this developer compared to Dektol. Thus exposures will need to be compensated.

[Jorge Gasteazoro]

Don, if the developer oxidizes after 4 hours, why not use MAS's trick and add a little of citric acid? I wonder what would happen if you add ascorbic acid? it is an antioxidant as well as a developer, you might gain some more contrast for azo 2.

Just a thought.

[Donald Miller]

Jorge,

That's certainly worth a try. I will add citric (since I have it on hand) and see what happens. I will let you know. I was going to ask you that question and just hadn't emailed you yet. I don't have ascorbic acid so I may need to order that in. Thanks for the suggestion.

[Jorge Gasteazoro]

Dont order it, just go to the drugstore and buy vitamin C, crush about 4 or 5 tablets and add them to the developer.