Author Topic: Radiation and photographic film  (Read 13408 times)

Offline ChrLz

  • Earth
  • ***
  • Posts: 241
Re: Radiation and photographic film
« Reply #15 on: May 28, 2013, 09:38:37 PM »
The hasselblad cameras were modified to deal with the static charge between the film and the camera. The scratch idea seems like a good one. The emulsion is very sensitive, especially when it's being processed, and is wet.
Yep.. - here is a thread on the old board - i think there's a more recent one somewhere.  You'll need to read down to get to the meatier bits:

http://apollohoax.proboards.com/index.cgi?board=theories&action=print&thread=2507

It's interesting as it dates back to 'GoneToPlaid's first appearance, and marks one of very few occasions when his first thought was not correct...  :D

Offline Allan F

  • Jupiter
  • ***
  • Posts: 896
Re: Radiation and photographic film
« Reply #16 on: May 28, 2013, 11:11:13 PM »
Seems reasonable enough.
Well, it is like this: The truth doesn't need insults. Insults are the refuge of a darkened mind, a mind that refuses to open and see. Foul language can't outcompete knowledge. And knowledge is the result of education. Education is the result of the wish to know more, not less.

Offline onebigmonkey

  • Saturn
  • ****
  • Posts: 1398
  • ALSJ Clown
    • Apollo Hoax Debunked
Re: Radiation and photographic film
« Reply #17 on: May 29, 2013, 12:53:09 AM »
One of the interesting things I discovered from looking at Lunar Orbiter photographs is how they photographed the moon.

The probes actually took and developed photographs in lunar orbit. The resulting images were scanned inside the probe and the data sent back by FM signals. So, if the radiation environment of the moon was so lethal to camera film, then these photographs would not exist. Apollo deniers often forget that the missions did not exist in isolation, and a long program of research and development preceded them, and that some of these supposedly insurmountable problems had actually been considered and worked around.

The main concern they had with the film was preventing it become rigid by being in the same place too long, and the 'Photo of the century' (a stunning oblique view of Copernicus crater) is claimed to be a product of taking a photograph purely out of the need to advance the film by a frame to keep things moving.

The Orbiter series also researched micrometeroid impacts, radiation levels under different types of shielding, gravitational differences, and allowed Earth-based radar tracking to be practised.

Offline Allan F

  • Jupiter
  • ***
  • Posts: 896
Re: Radiation and photographic film
« Reply #18 on: May 29, 2013, 06:47:48 AM »
By radar-tracking, I suppose you mean radio-based tracking? It would be a lot to ask for a skin-radar-return to be measurable at that distance.
Well, it is like this: The truth doesn't need insults. Insults are the refuge of a darkened mind, a mind that refuses to open and see. Foul language can't outcompete knowledge. And knowledge is the result of education. Education is the result of the wish to know more, not less.

Offline ka9q

  • Neptune
  • ****
  • Posts: 3000
Re: Radiation and photographic film
« Reply #19 on: May 29, 2013, 07:57:17 AM »
I'd have to dig up the actual reference, but I'm pretty sure I read that the Lunar Orbiter camera designers chose a very slow film specifically to minimize radiation sensitivity because their missions were much longer than Apollo. This drove much of the rest of the spacecraft design, as slow film tends to require long exposures, which can cause motion blurring if it's not compensated for.

Offline ka9q

  • Neptune
  • ****
  • Posts: 3000
Re: Radiation and photographic film
« Reply #20 on: May 29, 2013, 08:02:13 AM »
By radar-tracking, I suppose you mean radio-based tracking? It would be a lot to ask for a skin-radar-return to be measurable at that distance.
That's almost certainly true. Coherent transponders have been the standard since at least that time; they were the basis of Apollo tracking and they weren't new then.

For better or worse, the term 'radar' is often used for range/range-rate systems involving cooperative transponders. The "secondary surveillance radar" on aircraft is transponder-assisted, though it is operated in conjuction with a skin-tracking radar that can be used if the aircraft's transponder is not operating.

The Apollo LM's rendezvous "radar" also relied on a transponder on the CSM.

The only "true" radar that I know of on an Apollo spacecraft was the landing radar on the LM descent stage.

Offline raven

  • Saturn
  • ****
  • Posts: 1469
Re: Radiation and photographic film
« Reply #21 on: May 29, 2013, 11:14:43 AM »
It is worth noting Zond 5-8 (unmanned test versions of the Soviet equivalent of the Apollo 8 CSM) took film photographs and returned them to Earth as actual photographs. The means the radiation dosage would be at least similar to Apollo, having travelled through the Van Allen belts both ways.

Offline Dalhousie

  • Jupiter
  • ***
  • Posts: 527
Re: Radiation and photographic film
« Reply #22 on: June 07, 2013, 08:26:04 AM »
Luna 3 and Zond 3 also developed film onboard.

Offline raven

  • Saturn
  • ****
  • Posts: 1469
Re: Radiation and photographic film
« Reply #23 on: June 08, 2013, 09:14:24 PM »
Luna 3 and Zond 3 also developed film onboard.
As did the prosaically named Lunar Orbiter series.

Offline Dalhousie

  • Jupiter
  • ***
  • Posts: 527
Re: Radiation and photographic film
« Reply #24 on: June 10, 2013, 05:45:09 AM »
Luna 3 and Zond 3 also developed film onboard.
As did the prosaically named Lunar Orbiter series.
As already stated in reply 17...

Offline raven

  • Saturn
  • ****
  • Posts: 1469
Re: Radiation and photographic film
« Reply #25 on: June 10, 2013, 12:00:32 PM »
Luna 3 and Zond 3 also developed film onboard.
As did the prosaically named Lunar Orbiter series.
As already stated in reply 17...
Oops, my bad. I do know it was a fairly common system at the time, and was even used on some Mars probes I believe, at least on the USSR side of things.

Offline Dalhousie

  • Jupiter
  • ***
  • Posts: 527
Re: Radiation and photographic film
« Reply #26 on: June 11, 2013, 06:39:19 AM »
Luna 3 and Zond 3 also developed film onboard.
As did the prosaically named Lunar Orbiter series.
As already stated in reply 17...
Oops, my bad. I do know it was a fairly common system at the time, and was even used on some Mars probes I believe, at least on the USSR side of things.

;)

Zond 3 retransmitted the lunar images at Mars distance, whether this was the stored data or whether the images were rescanned I don't know.
I would assume that all earlier USSR probes also had the same system, although sadly they never had the chance to show their stuff.

Offline raven

  • Saturn
  • ****
  • Posts: 1469
Re: Radiation and photographic film
« Reply #27 on: June 13, 2013, 01:27:02 AM »
This page has some interesting info on Soviet space cameras.

Offline BazBear

  • Mars
  • ***
  • Posts: 381
Re: Radiation and photographic film
« Reply #28 on: June 19, 2013, 02:16:06 PM »
This page has some interesting info on Soviet space cameras.
Cool! Thanks for posting that link.
"It's true you know. In space, no one can hear you scream like a little girl." - Mark Watney, protagonist of The Martian by Andy Weir

My Youtube Apollo playlist http://www.youtube.com/watch?v=8SfyE9qsG8k&list=PL2aEC7cUMrGCNrtGMMWRXYob-kqCz2zz8

Offline raven

  • Saturn
  • ****
  • Posts: 1469
Re: Radiation and photographic film
« Reply #29 on: June 20, 2013, 12:55:24 AM »
My pleasure. :)