USSR Unibrom Another Batch

I bough this paper a while back and tried it out as part of my exploration of old photo papers.

USSR UniBrom Packaging

I ran a test strip as follows.

Unibrom f8 test strip

I developed as follows...

2 minute Ilford Universal PQ (1+9)
20 seconds stop
5 minute Ilford Rapid Fix (1+9)
30 minute wash

Already it looks low contrast. So I tried exposures at 32 seconds and 64 seconds at f8.

Unibrom f8 32sec

Unibrom f8 64sec

As suspected not very high contrast. So later I thought I would try out some Lith developer to see if I could get some better contrast from the paper as I did with the Agfa Lupex in the previous post.

So first a test strip using Moersch EasyLith developer.

EasyLith Unibom Test Strip

Hmm this was a mess. It developed very slowly at first. As with the Agfa Lupex I cut the test paper into partial strips after exposure so I could develop them individually. Suddenly the strips wnte from barely gray to very dark edges where I had cut the paper. These dark edges migrated rapidly to the center of the paper. I pulled them out at different times and hoped I could interpret the results.

I surmise that the developer had gotten into the paper through the cut edge of the emulsion and what I presume to be the infectious development of the Lith developer proceeded rapidly through the fiber in an uncontrolled manner. The normal edges of the paper show some evidence of this but the development seems to be stopped by the unexposed emulsion created by the easel blocking the enlarger light.

Below is a sample of the edge of the paper and below that the cut edges I made.

Paper Edge Scanned at 3200 dpi

Cut edges of paper scanned at 3200 dpi

It seems the developer moves along the paper fibers given the pattern above. So next I tried a print on a single uncut sheet.

Unibrom f4.5 240 sec exp 13 min develop EasyLith

OK now this was weird and I noticed it as I was watching for the snatch point to pull it from the developer. I was confused because the areas I would normally look to as dark to judge the development were not the darkest areas. Furthermore the lettering showed as lighter than the background; completely reversed. Somehow I got a negative print from a negative.

Further research and remembering an accident during the development explained this mystery. It is solarization. (see here for a good explanation) During development I was constantly moving my safelight closer to see the state of the dark areas. At one point the safelight came apart and the light from the bulb was allowed to shine on the developing paper. It was very close but very brief perhaps a second of time. This is textbook how one creates a solarized print (the linked article indicate 1-10 second second exposures). The print was curled and this may explain the lack of the effect on the top edge of the image.

I also exposed another print at 120 sec and developed it with more conventional results.

Unibrom f4.5 120 sec exp 13 min develop EasyLith

Here at least most of the areas expected to be white are lighter and the black areas are darker. There is ample evidence of overzealous development all over the print. Very strange. Perhaps a more dilute developer? I am not experienced enough to say what happened today in the darkroom.