Concentrated long lasting paper developer formula

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ruilourosa

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here it´s mono...

10gr Kbr + benzotriazole? or just kbr?

i will add some benzotriazole and try to find a good place for neutral tones avoiding fog

i think i managed to get 150gr of Sod. Carbonate into solution, but i really think that potassium hidroxide helped a bit, maybe just for heating the solution again



Thanks!!!!!!

Rui Lourosa
 

Ian Grant

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Well you should have added 173.4g Sodium Carbonate monohydrate, but as you added Potassium Hydroxide that'll make up for the difference. 5g Bromide with Benzotriazole, or 10g without.

Ian
 

koraks

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Ian Grant said:
actually the anhydrous is the commonest form in Europe.
Click to expand...
Not my part of europe, that's for sure. We get decahydrate and monohydrate, mostly. Anhydrous is also not a very good choice since it's gyroscopic and will a sorb moisture to become monohydrate, so with an opened container of anhydrous, you're never quite sure what the ratio between the two of them is.
If there's a choice I'd always recommend getting monohydrate; it's stable and most formulas are based on it (no conversion necessary).
 

Ian Grant

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Sodium Carbonate anhydrous is only very mildly hygroscopic, it takes years to deteriorate in a sealed container. Sugar is hygroscopic, as are a number of photographic chemicals like Potassium Bromide. It's not an issue.

Ian
 
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