t55 polaroid film-defects

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question regarding polaroid t55 film-- over the weekend, an imprompt shooting situation left me to put exposed t55 film in water for several hours before i immersed the film in sodium carbonate. the result has been puzzeling. one batch of film cleared and looked normal as i have done this once before. the second batch of film did not clear. a blackened image remained and the emulsion was very soft and became unattached to the gelatine film base. the dating on the film was 3/98-- a few months over the recommended time. is this the problem? thank you for your answers.

-- raymond a. bleesz (bleesz@vail.net), June 18, 1998


This might be completely offbase but is there enough of a chemical difference between Polaroid's recommendation of Sodium Sulfite and your use of Sodium Carbonate to be causing the problem you are having?

-- Ellis Vener (evphoto@insync.net), June 19, 1998.

You mentioned that you had been soaking your type 55 negatives in sodium carbonate. I sincerely hope that was not the case, and that you mis spoke in your message.

Sodium carbonate is a fairly strong alkalai as film chemicals go, and could very well have floated the emulsion off your negatives.

Polaroid's recommendation for Type 55 is a 18% solution of sodium SULFITE for Type 55 negatives, and a 12% solution of sodium SULFITE for type 665 negatives.

Sodium CARBONATE is washing soda.

-- Tony Brent (ajbrent@mich.com), September 08, 1998.

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