Monday, July 9, 2012

Keeping Pyrogallol developers

The question of storage, and keeping an ascorbate-soda deveoper has been raised again and again.

From early on, the notion was that under no circumstance should or would a develioper like that keep in solution.

More so, from the beginning it was stated that a developer like Caffenol should be used within half an hour after being mixed.

Not only is this wrong - it has probably caused errors or opened for errors in the unnecessary rush so created.

Other posts in this blog will underline what I write here, we have used Caffenol over and our for up to 10 times from a mix, stored for weeks, employing certain tricks.

The current state of affairs and my position on this is that Caffenol can be used to develop 3 times as much as originally advised, like for instance 400 - 500 ml (you loose a little volume with every film developed) of developer can be used safely to develop 3 films, provided it is withing a short timespaan, laike say 48 hours....

This means that up until now most users have thrown out countless gallons and litres of perfectly good developer..

I cannot precisely pinpoint why this came to be, I'd just like to go back in time, before the more modern developing agents was in use, before Metol, Phenidone and Hydroquinone was used, back when "natural developers" was in use.

From early on the developing agents came from surprizing sources, like from leather industries where chemicals used for tanning leather also was found to act as developers.

The stuff used shared a lot of things in common with ascorbate and caffeic acid, and most of the time those developers also was soda-based, like Caffenol.

Not only did they share natural stuff with us, they also faced the same problems, their developer had to be fresh mixed, and steps where taken to keep them.

I'd like to publish a picture here, from a Kodak publication to give a hint on how this was done by one of the major players

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