What is POP Paper?greenspun.com : LUSENET : Large format photography : One Thread
What is POP paper? I want to make contact prints, and my understanding is that this is a very slow paper. How do you use it?
-- William Marderness (email@example.com), March 08, 2000
Check out the website of Silverprint in London (http://www.silverprint.co.uk). They appear to be similar to our Bostick & Sullivan, selling materials for alternative photo processes. They have a paragraph describing Centennial printing-out paper that should help (there's a link to the Centennial POP on their home page).
'Centennial' Printing-out Paper
Printing-out paper, or POP for short is one of the transitional materials between Fox Talbots original paper and the modern enlarging materials we use today. It uses a silver/gelatin emulsion, but is not designed for developing; instead, an image is formed simply by exposure to light, being reinforced by an excess of silver nitrate carried in the emulsion. Very slow, it needs exposure to sunlight or UV light, using a negative the same size as the required image. The rewards of the process are the subtle qualities of the image, both in well separated tonal scale and colour. Printing-out results in self-masking, that is as the shadows increase in density, so this acts as a filter to light, slowing further shadow build-up, while the highlights print in. The image colour initially is a reddish purple. This is unstable,and although it can be kept for a long time if only occasionally inspected in low light, it is usual to want to permanise it. A slow sodium thiosulphate based fixer can be used on its own, resulting in an attractive amber colour, but for best effect gold toning should be used, which will preserve most of the original colour, tending only to shift it to a more cool purple.
-- Greg Lawhon (firstname.lastname@example.org), March 08, 2000.
William: Back in the early '60s we still used POP paper for making contact prints for studio proofs when we shot portraits on split 5x7 film. We contacted the proofs by putting them in a contact frame and setting them out in the sun. Not only was it an easy method, but the proofs would soon fade, so the customers would not keep them and not return or copy them and make the studio the loser. I haven't seen POP paper in years and I haven't missed it. There are lot better papers available.
Hope this helps. Doug.
-- Doug Paramore (email@example.com), March 10, 2000.
See also http://www.f32.com/Articles/art014.htm for several pages on POP and how to process it.
-- Chris Patti (firstname.lastname@example.org), March 10, 2000.