negs for POP

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starting in november i will be living in tokyo for 14 months . . . without access to a darkroom. i've decided this will be a great time to explore printing out paper (POP) and possibly some other alternative process that utilize the sun as a light source for printing.

i've been doing some research, and have learned that the best negative for POP is most likely from a film capable of a long tonal range that is overexposed and overdeveloped. very dense.

now the problem i have is where do i get started here. i've always used APX. and have grown to love efke 25. but APX is no longer available and efke 25 (as far as i know) is not available in 4x5. and my research suggests that TMX or fp4 is best anyway (the centenial POP faq says so) - both films i'm not familiar with. to top it off i love rodinal (its the cheapest thing out there and agfa products have never ever done me wrong + its easy + the whole cache of being the oldest manufactured developer. very cool. and BAMO! acutance is something like a very dry martini).

so who out there has been working with POP? what film/developer combo do you use to get the best POP negatives? is TMX in rodinal a done deal? what about this new fuji acros? i know everyone loves pyro. but i'm not sure if i'm ready to make that leap. worried that it maybe difficult to get pyro in japan (don't speak japanese). and just how great is this pyro anyway? will pyro negs help me do POP? if so, i'm there. so what do you all think? how do i get the best negs for POP? the less i have to fool around (though i know its valuable) the better.

thanks in advance. cheers.

-- James Luckett (jl@mollymail.com), August 22, 2001

Answers

James, I know very little about POP. If you don't get an answer on this forum you might have better luck with the Alternative Processes forum.

http://greenspun.com/bboard/q-and-a.tcl?topic= B%26W%20Photo%3a%20Alternative%20Process

-- Joe Miller (jmmiller@poka.com), August 22, 2001.


I've toyed around with salted paper, which is a POP process. Printing out processes do not require development of a latent image - the paper blackens automatically on exposure to light (it still needs to be fixed to make the image permanent though). Yes, POP paper accomodates a much longer density range. The basic reason for this is that the paper is self masking. If you use a contact printing frame, you can see the process at work by opening the back. In the shadows, density will appear readily but the deposited silver tends to slow down the emulsion in these areas by masking the light - this is what is meant by the self masking process. So the shadows take a long time to develop to a good black, which gives enough exposure to the highlights. As a result of this self masking, the paper accomodates a very long density range. Depending upon whether you are going to buy POP versus coating a paper yourself, you might have some room for play. For example, if you're coating your own paper, dichromate can be used to increase contrast a bit.

Now obviously, you getting the required negative needs expansion i.e., overdevelopment. The problem with overdevelopment is that it tends to increase grain. Now personally, I think this whole bit is a little over reacted to because this is a contact printing process - the grain would be more likely problematic with an enlarging process. But the consensus seems to be that overdevelopment does not work as well as it used to. In any case, that is the reason for the popularity of staining developers like pyro and pyrocatechin with such processes. Pyro is a staining developer. So part of the density comes from the stain. Since that is the case, the silver image itself needs to be developed to a lower contrast index, which thereby allows you to avoid the graininess that comes with overdeveloping the silver image. Of course, pyro has a bunch of other advantages also including the fact that it is a sharp developer (creates adjacency effects), makes developing by inspection easy etc. You could buy the necessary powders and mix up the developer if you want. The powders should be easy to take with you. Keep in mind that pyro is quite toxic and use appropriate caution in using it. Having said that, I see no problem with utilizing materials you are familiar with for the overdevelopment. Another option is to buy film and developers you are comfortable with and develop them the normal way. Then make a duplicate negative which is overdeveloped. A couple of advantages to this. One, you can have negatives for each process. Two, you get a little more points of control to tweak the neg for the POP process. You could buy some Kodak SO-132 direct duping film or buy some lith film for making the second negative. Lith film will develop to a fairly high density range quite easily.

Good luck, DJ

-- N Dhananjay (ndhanu@umich.edu), August 22, 2001.


James, I don't know if this will suite your taste and requirements, but I recommend investigating making digital desktop negatives. Here is a link to my short, one pager on this with a link to Dan Burkholder's web page, which is a must.

http://christianharkness.tripod.com/digitalnegative.html

I recently printed a digital negative on POP from Chicago Albumen works and was extremely satisfied with the results. It was an 8x10 print make from a black and white print scan originally shot with 35 mm b&w film.

chris

-- Christian Harkness (chris.harkness@eudoramail.com), August 22, 2001.


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