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« Last post by JayUtah on October 01, 2024, 05:23:53 PM »
Everything outgasses in vacuum.
The way Estar film bases handle this is to be very thin (say, 0.0025 in) so that all the outgassing that's going to happen happens early. It's not as if things outgas indefinitely. It's a half-life phenomenon. Estar is basically polyethylene terephthalate, commonly referred to as PET. It is used in practically every commercial sector (e.g., "plastic" soft drink bottles) and its properties are well known. Notice how none of the zillions of properly educated materials scientists are questioning the Apollo photography.
The Kodak SO-135 and SO-136 emulsion types were specifically hardened to expand their useful temperature range and further tweaked to increase evaporation and outgassing rates. Again, you can't stop the emulsion from absorbing water and then outgassing it later. The point is to have that happen very quickly, so that you aren't bothered by it later. Keep in mind that the processing of these films involved aqueous solutions. Drying time was a factor. These emulsions are specially intended for high-altitude and vacuum use, and are approximately half as thick as the ordinary emulsions on consumer Ektachrome. All the outgassing that's going to happen will happen early.
The lunar surface magazines were kept in the LM's MESA, exposed to vacuum during the entire outbound journey. They were not gas tight. By the time the astronaut removes the dark slide and attaches the magazine, there's simply nothing left to outgas.
Also, it's not clear by what mechanism outgassing is claimed to ruin photography. It's a non sequitur. Yes, things outgas. Why would this result in photography not being as shown?