Quote Originally Posted by Roger Hicks
I seriously doubt that many ISO 400 films can deliver enough contrast for POP in anything. For POP I use Ilford FP4 Plus and Ortho Plus, both of which can be developed to a high gamma in almost anything.

Roger (www.rogerandfrances.com)
Since POP is primarily a UV sensitive process you can get a lot more effective printing contrast with most films by developing in a staining developer. I would recommend a 5:3:100 dilution of Pyrocat-HD.

If the scene you are photographing is one of normal contrast you can get plenty of contrast for POP with most ISO 400 films, including HP5+, TRI-X 320 and JancC 400. However, if you are photograhing a low contrast scene the only ISO 400 film (that I know) that will give you enough contrast for POP is TMAX 400.

If you can live with its speed Ilford FP4+ is an excellent film for developing to a high CI.