Sunday, July 23, 2017

Moving Forward in Reverse

If you read my article on lumen printing, this is sort of an addendum or appendix or epilogue or sequel. I had the paper cut, but for the lumen prints, I had cut it in sort of dim diffuse room light, so those pieces are really only good for lumen printing since they are a bit exposed already. So I went and cut some more 8x10 Agfa Multicontrast paper under my red led headlamp (hung about 30" above the work surface). Those pieces went directly into film holders. I had read about reversal processing film a while back (reversal processing is how slides or transparencies are made) and was sort of interested, but the bleach put me off. Most reversal process bleach is made with dichromate or permanganate compounds which are pretty toxic and best avoided if possible. So I shelved the idea of diy reversal. Then I read an interesting article about a fellow who made a working reversal bleach with just household hydrogen peroxide and lemon juice (the active ingredient there being citric acid). WHAT!? This I've got to try. I didn't have any film ready to develop, so why not try with the papers? It's more or less the same emulsion, just with a different base and in the case of RC paper like mine, a different top coat. What the heck, let's just experiment!. The article called for caffenol for the development steps, but I didn't have any of that ready to go. I did have some homemade my-tol(X-Tol knock-off), so I figured I'd just use that at stock concentration and see what happens. I read on APUG that you can develop paper with X-Tol stock for about 5 minutes, so that's where I started. Here is an overview of the process I used (note, I used 9g/L dry citric acid in place of lemon juice):

1st developer (my-tol)5 min
Wash5 min
Bleach (cit. acid-hydrogen)11:30 min
Wash5 min
Re-exposure 300W at 1 meter2:30 min
2nd developer (my-tol)5 min
Wash5 min
Fixer5 min
Final Wash5 min
Wetting agent2

The first sheet I did with straight stock my-tol for 5 min in both development steps. Here it is. This is a straight color scan without any added colors, curves or contrast.

A couple of notes worth making here... I was tray developing under red light so I could see what was going on. After a couple of minutes in the first developer, the paper looked completely black. I couldn't see any image at all. I was a little worried, but I kept going because I knew that this was not necessarily an indication of failure yet. The bleach brought out a little bit of an image. I could just make out some light areas. Once I turned on the room lights for the re-exposure step, I could tell that the image was there still. It looked bad and was very low contrast. I thought, "well I guess I'll have to correct it in post." That's not what I was hoping for with this process, but sometimes that's all you get. But then I poured in the 2nd developer (same developer as I used in the first developer step) and there was the image, nice and crisp and contrasty in tan and deep black. That is when I got excited. The fixer didn't change the image since there really isn't any undeveloped silver left at this point.

The next set of exposures I did with 1:1 my-tol, thinking that I might lower the contrast a bit. Unfortunately, I was tray developing these together in an under-sized tray and so there are artifacts where the sheets contacted each other. But these are experiments, not art. What I was trying to see was whether the dilute developer would lower contrast. I don't think it did. Maybe more dilution or a different type of developer (vit. C based like caffenol or parodinal) would work. Maybe something as simple as preflashing the paper would work. These are all variables that can be explored.

So there you go. I think I really like this process. If anyone else has experience and wants to share some tips, please do!