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Post by markc2511 on Dec 16, 2010 16:04:26 GMT -4
Hi guys,
Just after joining and I have a quick question on the type of film used in the Apollo missions. It has been put to me on another message board that this type of film could not have produced the results that it did in Nasa's photos.
His argument is that the film has a very narrow dynamic range, the ev value between the highlight and shadow is way out of range of this type of film, it simply cannot record both highlight and shadow and keep detail, ask anybody on a photography forum, who has experience of shooting with transparency film and they will tell you a 2nd light source had to be used on apollo missions.
I have no expertise in photography but perhaps some of the posters here can say if he is talking bull or not.
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Post by gillianren on Dec 16, 2010 16:23:15 GMT -4
Ask him how a second light source would avoid doubling the shadows.
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Post by markc2511 on Dec 16, 2010 16:36:36 GMT -4
He dealt with this already apparently a slight tweak and those shadows would not appear, (ie: increase the backlight slightly)
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Post by echnaton on Dec 16, 2010 16:40:43 GMT -4
There was more than one source of natural lighting in the photos, of course. The astronauts were lit by reflections from the surrounding terrain in all cases of by from the LM or the astronaut taking the photo in some pictures. So to get a better handle on their real claim, you need to do is ask them to demonstrate where the second light source is for every photo in which they claim it is present. After they refuse or fail at that task ask them for a citation for a qualified photo analyst that backs them up. Ask them to reconcile the video of the moon walks with claims of two light sources. You can learn more by visiting the photo section of clavius.org
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Post by gillianren on Dec 16, 2010 16:47:45 GMT -4
He dealt with this already apparently a slight tweak and those shadows would not appear, (ie: increase the backlight slightly) So the shadows should then all fall forward. I'm not familiar with the entire Apollo record, but that isn't the case. And I have to tell you, I don't think he's right in any case. Ask for a demonstration. Remember that the burden of proof is on him.
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Post by markc2511 on Dec 16, 2010 17:06:53 GMT -4
There was more than one source of natural lighting in the photos, of course. The astronauts were lit by reflections from the surrounding terrain in all cases of by from the LM or the astronaut taking the photo in some pictures. So to get a better handle on their real claim, you need to do is ask them to demonstrate where the second light source is for every photo in which they claim it is present. After they refuse or fail at that task ask them for a citation for a qualified photo analyst that backs them up. Ask them to reconcile the video of the moon walks with claims of two light sources. You can learn more by visiting the photo section of clavius.orgCheers for this. He actually claims to be a photography expert himself with twenty years experience of using this type of film. He maintains that is vry difficult to use in direct sunlight. He does acknowledge that some light is reflected from the surrounding terrain but he maintains it wouldnt be enough to light up the astronauts to the degree that they are in nasa's photos. I may be the wrong guy to debate with him unfortunately
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Post by markc2511 on Dec 16, 2010 17:10:28 GMT -4
He dealt with this already apparently a slight tweak and those shadows would not appear, (ie: increase the backlight slightly) So the shadows should then all fall forward. I'm not familiar with the entire Apollo record, but that isn't the case. And I have to tell you, I don't think he's right in any case. Ask for a demonstration. Remember that the burden of proof is on him. He has given a couple of examples of this on earth but its debatable that the conditions would be the same as the moon. I found it interesting that he questioned that type of film couldnt produce these photos and was wondering had it been discussed here before?
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Post by echnaton on Dec 16, 2010 20:09:28 GMT -4
Cheers for this. He actually claims to be a photography expert himself with twenty years experience of using this type of film. He maintains that is vry difficult to use in direct sunlight. He does acknowledge that some light is reflected from the surrounding terrain but he maintains it wouldnt be enough to light up the astronauts to the degree that they are in nasa's photos. I may be the wrong guy to debate with him unfortunately Well as a personal authority on the subject, he should easily be able to provide some references that back him up. He should also be able to provide references that indicate that he is a recognized authority on the properties of the film. If he cannot, then he is just another guy says "trust me." His personal experience is meaningless unless his work is peer reviewed. Ask him for his publications and peer recognition in the properties of film. We know he doesn't have any, so don't let him baffle you with techno jargon. Make him prove his case.
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Post by fiveonit on Dec 16, 2010 21:09:07 GMT -4
... don't let him baffle you with techno jargon. Make him prove his case. Indeed! One thing I always ask these self declared "Professional Photographers" that claim proof of a moon hoax is this... If you're such a great professional and have all this experience in photography, then why haven't you re-created these shots in a studio to show the world how they can be faked? They always have to go into these arrogant screeds about how it could be easily reproduced in a studio with multiple lights and fill lighting, yet they NEVER GO AND DO IT!
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Post by AtomicDog on Dec 16, 2010 21:30:43 GMT -4
Ask him, what is the dynamic range of Kodachrome. Then ask him what is the dynamic range of Ektachrome, which is the type of film that was actually used on Apollo.
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Post by tedward on Dec 17, 2010 5:38:46 GMT -4
20 years? I have been using a camera for longer but would not call myself an expert in camera's. I can use them but would struggle to point out how the lens or film works with some crib notes. Ask for the work if he is so qualified.
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Post by peterscreek on Dec 17, 2010 17:40:07 GMT -4
I'm an experienced photographer, although it's been quite some time since I've worked with slide film. I've shot both Kodachrome and Ektachrome and as I recall, they have similar dynamic ranges of around 8 stops. Where they differ markedly, is exposure latitude. Ektachrome was much more forgiving of exposure errors while Kodachrome demanded greater accuracy. Fill lighting helps reduce the dynamic range of a scene but does nothing to increase exposure latitude.
As previously mentioned in this thread and in many, many others on this forum, reflected fill light was provided by the regolith, the LM, and the astronauts themselves. It's true that the regolith is relatively dark but it has some interesting optical properties that most photographers aren't aware of. The Clavius site has more detail on that.
Dark as it is, I've taken many a shot by the light reflected from the surface of the Moon.
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Post by gonetoplaid on Jan 4, 2011 11:00:30 GMT -4
I concur that Ektachrome was more forgiving compared to Kodachrome regarding exposure errors due to Ektachrome's nonlinear response at both ends of its response curves. As for the regolith albedo properties on the surface of the moon, a similar earth-based example would be to take photographs in a large dew covered grass field. The dew on the grass nicely recreates the Heiligenschein (produced by the tiny glass beads in the lunar regolith) effect seen in Apollo EVA photographs.
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Post by Jason Thompson on Jan 4, 2011 11:38:33 GMT -4
He does acknowledge that some light is reflected from the surrounding terrain but he maintains it wouldnt be enough to light up the astronauts to the degree that they are in nasa's photos. I may be the wrong guy to debate with him unfortunately So the Moon's surface can reflect enough light to allow us to read by it here, 250,000 miles away, but not enough to be a suitable fill light to someone actually on the surface?
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Post by banjomd on Jan 4, 2011 12:16:11 GMT -4
Nice one, Jason (touche')
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