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Ulophot
19-Dec-2022, 18:43
An intriguing result came from a foolish error made tonight while continuing a series of tests on 2-solution development using D-23. I have been using a carefully created, 3-D test target to render flat tonal areas from Zone I minus 1/3 to VIII or greater ( or VIII and lower Zone 0) depending on how it’s lit. All prints, of course, are made at the same contrast, magnification, and exposure time, for comparison.

In the test tonight, I had two negatives, exposed to the target with the minus-I to VIII lighting, which I had overexposed to place the Zone VIII tone on XII, i.e., Zone III-ish to XII with Normal development. Having achieved an N-3 previously using D-23 stock, I thought I’d see what would happen with my usual dilution of 1:1.

The first negative got 3 minutes of constant agitation in Bath A, and 3 minutes of sitting in B (Borax solution). The result was about N-5 with the lowest values somewhat depressed. The next negative received 5 minutes of constant agitation, a bold 60% increase -- and then I made my error. Instead of Bath B, I mixed up beakers and poured in water, which then sat for 2 ½ minutes before I realized my mistake. I decided to proceed anyway, poured out the water and poured in Bath B for three minutes of sitting.

The resultant negative is very dense. By that I mean, at the same print exposure, VI is IX, II is V, and even minus-I is a III, indicating significant overall fog in addition to the development’s density increase -- although, the image has no appearance of fog as it might from, say, pre-exposure, because the low values are well separated from falling higher on the scale. in printing it, takes a 60% increase in exposure time to bring the exposed XII to print IX, exposed IV to print IV, and exposed minus-III to about I.

So, I was surprised. After reading cautions against a water rinse between the two baths. In this case, the water apparently acted as a still water bath, allowing development to continue especially in the low values, and the subsequent proper Bath B boosted the process further. I somehow expected the developer to have diffused into the water so that the Borax would have less to accelerate.

Any thoughts from others more chemically astute than I on how this worked?

Graham Patterson
20-Dec-2022, 10:07
I think you will have to reproduce the result deliberately, first. Just to be sure that what you think happened, did, and get it documented.

The film stays in the tray while the solutions are exchanged, and not moved between different trays? Emulsion up or down? I can think of some things which might affect diffusion, but I am not sure if they would apply in this case.

Ulophot
20-Dec-2022, 11:36
ACtually, Graham, I'm using a Stearman 4x5 tank. I had concerns that pouring in Bath B would create issues, but after reading that some users agitate in Bath B as well as A, I gave it a try and I have yet to notice any problems yet.

I will confirm when I get a chance; but there's no other possibility I can think of with the graduate I had, what was in them, and the procedure I followed.