Pyro

[Curt]

Is anyone making their own Pyrocat-HD and where do you obtain the Pyrocatechin?​

Pyrocat-HD
Stock Solution A​

Distilled water

75 ml​

Sodium metabisulfite

1 g​

Pyrocatechin

5.0 g​

Phenidone**

0.2 g​

Potassium bromide

0.2 g​

Distilled water to make

100 ml

Stock Solution B​

Distilled Water

70 ml​

Potassium carbonate

75 g​

Distilled water to make

100 ml​

 

[nworth]

Pyrocatechin (catechol) is available from Photographers' Formulary and probably others.

 

[skahde]

What really bugs me is the abundance of differing formulas for pyrocat hd. I confess to be guilty to have made my own but it really gets difficult to part variations from typos. 0.2g bromide??? Unblinkingeye says 0.1g http://unblinkingeye.com/Articles/Developers/Formulas/formulas.html

best

Stefan

 

[jordanstarr]

I get mine from JD Photochem in Quebec from a woman named Claire. $12.00/100g or $18/250g. The chemical would probably expire before you were able to use it all though I would imagine. I'm not sure if you can get this shipped to the USA though across the border, but I see no reason why not if it's from an accredited photo store.

 

[Ian Grant]

There are a lot of people making up their own Pyrocat HD, Pyrocatechin is readily available from a wide variety of sources because it also has uses outside photography.

Sandy King's article on Unblinkingeye gives various variations to the formula.

Ian

 

[Bounty]

Hi, you can buy Pyrocatechin from artcraft chemicals.inc in the USA, go for it, Bounty

 

[skahde]

Sandy King's article on Unblinkingeye gives various variations to the formula.

Based on the variations in the original recipe and Sandy's variations 1g/L Bromide is the correct concentration. But in view of the variations issued later on from different sources I was a bit concerned there might exist some source, publishing another variation with more Bromide under the label of Pyrocat HD.

Well, I think it's a typo.

Stefan

 

[john_s]

You can leave out the bromide.

 

[T Hoskinson]

You can leave out the bromide.

Yes, I leave the KBr out (with good results).

 

[PhotoJim]

Be careful using the word "pyro". Historically it referred to pyrogallol, which is an entirely different chemical (although it does share some qualities with pyrocatechin).

I got my pyrocatechin from a mail order chemical house in Montreal. Photographer's Formulary in Montana also has it, and I imagine Bostic & Sullivan does as well.

 

[gainer]

Pyrocatechin or catechol is 1,3 dihydroxybenzene. Pyrogallol (pyro for short) is 1,2,3 trihydroxybenzene. Hydroquinone is 1,4 dihydroxybenzene. You can see they are all related. Catechol and hydroquinone have the same molecular weight and the same number of OH groups on each benzene ring, but they look and smell different and produce different stain colors when used with little or no sulfite. With enough sulfite, catechol may be used as an expensive substitute for hydroquinone in a non-staining developer.

 

[Curt]

Be careful using the word "pyro". Historically it referred to pyrogallol, which is an entirely different chemical (although it does share some qualities with pyrocatechin).

Thanks to all, this information clears up the chemical question.

Curt