Re: Sterling contact paper?
----- Original Message ----- From: "Panmedia" <panmedia@comcast.net> To: <alt-photo-process-l@usask.ca> Sent: Wednesday, November 07, 2007 7:40 PM Subject: Re: Sterling contact paper? Thanks I may ask a few people running a test for me for this paper. I thought about taking the whole lot but only if the paper is still usable.The shelf life of paper is quite variable and also depends on how its been stored. The cooler the better. About the only way to find out if the paper is still good is to try it. Paper looses sensitivity and contrast with age and picks up fog. In general, the slower the emulsion the better it takes aging, but again, paper varies. Test for fog by fixing out an undeveloped sample of the paper and comparing it to one that had been developed. After washing they should be the same. Slight fog can usually be cured by adding some anti-fog to the developer. Potassium bromide works OK but benzotriazole is better because it is a more effective fog suppressor but doesn't loose as much paper speed as bromide. Unless you want to print using a printing box there is really not much purpose to contact paper. One can make perfectly acceptable contact prints using enlarging paper and a weak light source. Most of the virtue of contact printing comes from the method rather than the paper. The persistent idea that contact paper has a longer range of densities or better gray scale rendition than enlarging paper is based on the materials of some seventy five years ago. Modern enlarging papers have a greater maximum black than the old papers of any type. Tone rendition is a characteristic of the particular paper, it varies all over the place. Negatives for contact printing on "normal" grade paper need to be more contrasty than those for condenser enlargers but about the same as for diffusion enlarging. The last contact paper made by a major manufacturer was Azo, made by Kodak. Azo was a silver chloride emulsion. Kodak made a paper with that name from the 1920's, maybe earlier. They bought the company who originally made it. Azo was intended for general purpose industrial and professional photography IMO there was never anything special about it. For many years Kodak also made a very warm tone contact paper called Athena and a blue-black fast contact paper for photofinishing called Velox. From my experience Velox was unique in having a truely blue-black image. Ansco and Defender also made at least two contact papers each, usually a cold tone and a warm tone one. In any case, Freestyle has Foma contact paper in stock. However, it is an RC paper with matt surface, not quite what fans of contact printing want. --- Richard Knoppow Los Angeles, CA, USA dickburk@ix.netcom.com
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