Diafine: substitute Metol for Hydroquinone ?

[Ken Lee]

I found the following formula for Diafine, and I have all the ingredients except Hydroquinone.

Could we substitute Metol for Hydroquinone ? If so, how much please ?

Thanks in advance

Solution A:
Water at 125F/52C 750 ml
Sodium sulfite, anhydrous 35 grams
Hydroquinone 6 grams
Phenidone 0.2 grams
Sodium bisulfite 6 grams
Room temperature water to make 1.0 liter

Solution B:
Water at 125F/52C 750 ml
Sodium sulfite 65 grams
Borax 20 grams
Cold water to make 1.0 liter

[Erik Larsen]

I don't believe so, but I think you could sub the phenidone with metol
Not very helpful, sorry.

[Gem Singer]

Ken,

Hydroquinone is a high contrast developing agent, like Pyro

Metol is a low contrast developing agent, like Phenidone.

Using Metol + Phenidone in that formula will probably result in a very low contrast negative.

[Sevo]

The real problem is that the Hydrochinone in MQ developers interacts with the Metol type other developing agent (in your case, Phenidone) - I am not aware of a Metol/Phenidone developer, as the Metol in that mix would be redundant.

[sanking]

I found the following formula for Diafine, and I have all the ingredients except Hydroquinone.

Could we substitute Metol for Hydroquinone ? If so, how much please ?

Ken,

Substitution of metol for hydroquinone would result in a very low contrast developer, barring some type of unexpected synergy between metol and phenidone.

You may be able to substitute pyrocatechin for hydroquinone in this formula since these reducers are somewhat similar in contrast and working pH, and both should be synergistic with phenidone.

Sandy

[Sevo]

Ken,

Substitution of metol for hydroquinone would result in a very low contrast developer, barring some type of unexpected synergy between metol and phenidone.

Phenidone is self-inhibiting (hence there are no solitary Phenidone developers I am aware of) and that will probably extend to Metol.

[Gem Singer]

Sevo,

Look up POTA Developer (the "P" stands for Phenidone). Very low contrast developer.

It was used for negatives that were exposed to the bright flash of an atomic bomb explosion.

D-23 is a developer that only contains Metol as it's developing agent.

[Leigh]

Why not just buy Diafine?

Mixing our own rather than buying commercial is a great way to put companies out of business.

- Leigh

[Sevo]

Sevo,

Look up POTA Developer (the "P" stands for Phenidone). Very low contrast developer.

It was used for negatives that were exposed to the bright flash of an atomic bomb explosion.

You are of course right - I've even used it, to tame Technical Pan and other ultra-high contrast process films.

D-23 is a developer that only contains Metol as it's developing agent.

Metol developers aren't (or weren't) that rare - most makers used to have one, often described as "softer paper developer" in their recipes. But Metol is nowhere as self-inhibiting as Phenidone (while the latter seems to inhibit Metol as well).

[Ken Lee]

For the record, I saw Sart S's still-life photos today, and it reawakened my interest in divided developers.

Divided Pyrocat HDC is great, but I like to experiment from time to time, so thought I'd give Diafine (or something like it) a try.