PMK alternate dilutions

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Has anyone tried diluting PMK? I'm talking about 1/2 to 1/4 its normal working concentration (1:2:100).

I've been working on a developer formulation based on catechol and lately I've been doing some testing with higher dilution ratios. My results have yielded smoother total gradation, lessened grain clumping and remarkable sharpness. So it occurred to me that similar effects might result with more dilute PMK. Does anyone have any experience with this?

In his book, GH suggests the PMK ratio is not cast in stone, and, in fact, offers a 1:2:50 ratio to increase speed and contrast. I don't recall, however, him saying much about higher dilutions.

-- Ted Kaufman (writercrmp@aol.com), June 26, 2001

Answers

I tried a ratio of 5:10:1000 and the film did not stain and barely developed. On page 44 of the Book of Pyro it says to add water and do not reduce the developer amounts to dilute the developer. My developing tank can't hold more than 1000 ml of solution so I decided not to experiment with the developer's dilutions. According to the book the developer amounts is increased, I don't know if reducing the water will have the same affect.

-- David Payumo (dpayumo@home.com), June 26, 2001.

Hello. I have used PMK for tech pan as follows: 1 1/2ml A, 24 ml B and 600 ml water. this is for one 120 roll. 8 min. @ 69 f. It is the closest to good results with tech pan. But I have been using PMK for a number of years and if necessary will try different dilutions, it is a very flexible formula. Hope this helps.

-- Marcel Perez-Calisto (marcelperez@hotmail.com), June 27, 2001.

Thanks for your responses. Marcel, that sounds pretty good for Tech Pan. I think I'll try it.

David, you can reduce parts A, B, and water proportionally and maintain the integrity of the formula. For example, 5:10:500 is the same as 10:20:1000, just less of it. I was asking about varying either the A or B ratio(s) to water for compensation, or full development with lowered contrast.

-- Ted Kaufman (writercrmp@aol.com), June 28, 2001.


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