mono bath

[estudleon]

Hi. I want to use a monobath formula.

Which phenidone I have to use ?

A) Phenidone A (1 Phenyl 3 Pyrazolidone)
B) Phenidone B (4 Methyl 1 Phenyl Pyrazolidone)

The formula is :

Phenidone 4 grs.
Hydroquinone 12 grs.
Sodium hiposulphite 110 grs.
Sodium hidroxido 4 grs.
Sodium anhydrous sulfite 50 grs.

Thanks.

Rino

 

[srtiwari]

A) I believe.

See 4th line of second response....

http://photo.net/black-and-white-photo-film-processing-forum/00V4rD

 

[Freakscene]

Either should work. if you buy "phenidone" it is usually phenidone-A. There are differences in activity and susceptibility to oxidation among phenidone and dimezone variants, but this just means minor changes in developing time in the same developer made with the different variants. It may make more difference for a monobath, however, so I'd stick to phenidone-A.

Marty