Author Topic: Apollo 11 film test in a vacuum.  (Read 282 times)

Offline apollo16uvc

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Apollo 11 film test in a vacuum.
« on: October 04, 2017, 08:52:44 AM »
I would like to know what the psi of the LM was before depressurization.
How long it took to completely depressurize.
How long it was depressurized.
How long it took to re pressurize and to which psi.

Some people want to test film in a vacuum so I am writing an experiment for them that matches the Apollo 11 situation as closely as possible.

Does anyone know what kind of lubricant was used in the NASA Hasselblad 500EL/M cameras? normal lubricant may boil off. Does anyone know to which extend this could inhibit a mechanical camera and film?
 
Normal Hasselblad 500EL/M cameras could be powered by batteries or by a cable. How did nasa power them? if they used a battery, which kind?

Which film stock was used?
« Last Edit: October 04, 2017, 09:41:46 AM by apollo16uvc »
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Offline Kiwi

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Re: Apollo 11 film test in a vacuum.
« Reply #1 on: October 06, 2017, 10:13:08 AM »
I would like to know what the psi of the LM was before depressurization.
How long it took to completely depressurize.
How long it was depressurized.
How long it took to re pressurize and to which psi.

Some people want to test film in a vacuum so I am writing an experiment for them that matches the Apollo 11 situation as closely as possible.

Be patient - it's quiet here without the number of hoax-believers we used to have, so members turn up a little less frequently. Have a look at Jay Utah's website Clavius (link on the home page) where he has information about the cameras and film.

Sometimes your questions have made me wonder whether you use the same three resources that many of us use for information, The Apollo Lunar Surface Journals (ALSJ), The Apollo Flight Journals (AFJ) and "Apollo By The Numbers."

I've just had a quick browse at everything that happened as it is described in the ALSJ a bit before and up to full depressurisation of Eagle the first time on the lunar surface, which took a much longer time than originally expected.

The relevant figures you want are not set out in a table, but they're there, including a hint that the first figure you want was 5 PSI, but I don't know if that is accurate. The only expertise I can bring to unravelling Apollo is experience in non-scientific photography around the 1970s (occasionally my experience, such as how negatives were numbered back then, bettered the opinions of more modern photographers) and also experience analysing photos for photography-shop customers around then and since as an occasional photography competition judge.  But I don't know much about rocketry and all the other sciences.

Some things at the ALSJ that are most valuable are the comments by editor Eric Jones, Neil Armstrong, Buzz Aldrin and other experts.

The section to start in for Eagle's first depressurisation (search for "depress" only) in the ALSJ is "EVA Preparations" and the ground-elapsed time (GET) of 108:53:00, but there are little bits of information right back at 108:21:50 and sometimes long gaps until there is more.

The Apollo Lunar Surface Journals (ALSJ)
https://www.hq.nasa.gov/office/pao/History/alsj/frame.html

The Apollo Flight Journals (AFJ)
https://history.nasa.gov/afj/

"Apollo By The Numbers" by Richard W Orloff
https://history.nasa.gov/SP-4029/SP-4029.htm
has a gazillion numbers that would please any pedant (which I am :-)), but it's not so easy to get around the online version due to some faulty and missing links. Thanks to the incredible generosity of fellow member sts60 I have a hardcopy original of the book which he gave me, but I also made up useful links to every page of the online version which are posted on an older incarnation of this forum.

See this old thread for better links, and read beyond the first post to find some faulty or missing links:--
http://apollohoax.proboards.com/thread/1356/apollo-numbers

« Last Edit: October 06, 2017, 10:41:45 AM by Kiwi »
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Offline ka9q

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Re: Apollo 11 film test in a vacuum.
« Reply #2 on: October 07, 2017, 07:32:24 PM »
IIRC, the lunar surface cameras were powered by nickel-cadmium batteries.

I don't know what lubricant was used, but there are many with very low vapor pressures that are designed to be used in vacuum. Molybdenum disulfide is one.