An MPQ Developer.

[Keith Tapscott.]

There isn`t anything new about developers using three or more developing agents as can be seen in some of Geoffrey Crawley`s formulas.
This is the MSDS for Tetenal Ultrafin-Liquid developer.
I wonder how many other commercial developers use both Metol and a Phenidone type developing agent?

 

[Photo Engineer]

This developer contains 3 developing agents. Using just Metol with Phenidone is less effective than HQ with Phenidone. Using 3 developing agents is usually overdesign unless there is something special about the developing agent such as glycin or amidol.

PE

 

[Keith Tapscott.]

This developer contains 3 developing agents. Using just Metol with Phenidone is less effective than HQ with Phenidone. Using 3 developing agents is usually overdesign unless there is something special about the developing agent such as glycin or amidol.

PE

I meant to mention HQ in this product. The Phenidone is probably useless without it.
Their Neofin Blue high-definition developer also uses those three constituents as well.

 

[Photo Engineer]

Overkill according to my own experience and that of Grant Haist. OTOH, Glycin and Amidol change the playing field by quite a bit. You can use HQ and Phenidone or just plain Metol to great advantage.

PE

 

[Keith Tapscott.]

Overkill according to my own experience and that of Grant Haist. OTOH, Glycin and Amidol change the playing field by quite a bit. You can use HQ and Phenidone or just plain Metol to great advantage.

PE

Metol is probably the most versatile of any developing agent for B&W processing.

 

[Keith Tapscott.]

Using 3 developing agents is usually overdesign unless there is something special about the developing agent such as glycin or amidol.

PE

PE, in what respect is using both Metol and a Phenidone type with HQ in the same developer overkill?
My understanding from Crawley`s notes is that Phenidone helps to boost shadow details while Metol is softer working in the highlights. What are your own findings with an MPQ B&W film developer?

 

[Photo Engineer]

I agree, but making a concentrate that works like Rodinal is tough. It does not keep at high pH. In fact, Metol is pretty hard to stabilze under many conditions.

PE

 

[Photo Engineer]

PE, in what respect is using both Metol and a Phenidone type with HQ in the same developer overkill?
My understanding from Crawley`s notes is that Phenidone helps to boost shadow details while Metol is softer working in the highlights. What are your own findings with an MPQ B&W film developer?

Metol and HQ are superadditive, but then Phenidone and HQ are superadditive to an extent. So, you have 2 superadditive developers in competition. You really don't need both pairs unless you can prove an advantage. Grant showed me that there is generally no advantage. Metol alone is as good as you get (see your last post before this one).

So, you are really wasting some of the developing agents to no purpose and could get the same result from Metol alone, or close to it. Then by jiggering with the rest of the formula everything could fall into place.

PE

 

[Keith Tapscott.]

I agree, but making a concentrate that works like Rodinal is tough. It does not keep at high pH. In fact, Metol is pretty hard to stabilze under many conditions.

PE

That helps to explain why Metol only developers such as Beutler`s, FX-1, FX-2 and Ilford ID-3 are made up as two-part stock solutions. Thanks.

 

[Alan Johnson]

See Crawley's explanation for FX-4 quoted in the Film Developing Cookbook.Interaction of metol and phenidone inhibits development of highlights not shadows and gives a speed increase.

 

[Keith Tapscott.]

See Crawley's explanation for FX-4 quoted in the Film Developing Cookbook.Interaction of metol and phenidone inhibits development of highlights not shadows and gives a speed increase.

Alan, read my post again. Boosting shadow detail is increasing the speed and softer working in the highlights is inhibiting them, so the same meaning as you have explained.

 

[Jordan]

If I recall correctly, Ilfosol uses (or used) phenidone, ascorbate and hydroquinone. I always wondered about that.

 

[Keith Tapscott.]

If I recall correctly, Ilfosol uses (or used) phenidone, ascorbate and hydroquinone. I always wondered about that.

Yes, Ilfosol also contains (contained?) more than two developing agents, I almost forgot about Ilfosol. There must be a reason or advantage for using more than two agents, otherwise developers like Ultrafin, Neofin and Ilfosol would have been discontinued a long time ago. I`m sure that Roger Hicks mentioned something about this before on apug, but I cannot find it.