Thread: reversal prints
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Old 2nd December 2020, 12:10 AM
JOReynolds JOReynolds is offline
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Location: St Albans UK/Agde France
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Default reversal colour prints

It's much easier to reversal-process colour paper because all of the silver is bleached out, leaving only a dye image. In B&W, the desired image is contained in the silver produced in the second development, so you have to be careful not to bleach it out earlier in the sequence.

Once upon a time there was an Eastman Product processed in R100 chemistry. It wasn't very good, although it was better than the Ansco equivalent of the era. Then Kodak-Pathé Chalon-sur-Saône (France) came up with Ektachrome paper, vastly better and processed in four-bath R14. It was a replenished system and had a smelly acetic acid stop bath. Then came R3, a version with a water wash in place of the stop bath. There was a paper version with adjusted contrast for making copy prints, which you could use for photography in a large-format camera and loads of light. The water bath needed to start with an egg-cupfull of first developer in it to correct slightly pink highlights.

One weekend a colleague's processor was up to temperature and waiting for something or other to arrive and he tried making reversal prints with ordinary Ektacolor neg/pos paper. The results were way off at first and needed huge filter settings - but were promising. I don't have facilities for tests, so I'm not volunteering to start experimenting again but the fundamentals were sound.

In theory it only needs a straight PQ first developer, a stop bath [lights on from here], a stannous fogging bath or re-exposure and a rinse, some RA4 colour developer, RA4 bleachfix and wash.

There might be a contrast problem. Ektachrome paper was intended to make prints from transparencies (contrast gamma typically ~1.5) and if the paper contrast is 1.0 the prints will be way too contrasty, like Cibachrome.

Last edited by JOReynolds; 2nd December 2020 at 12:15 AM.
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