Author Topic: Getaway special for 9-11 conspiracy theorists  (Read 31773 times)

Offline grmcdorman

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Re: Getaway special for 9-11 conspiracy theorists
« Reply #60 on: August 02, 2015, 10:32:24 AM »
Yeah, I overlooked that. Spectography only works on actual materials; a reproduction of an image is necessarily altered (it only produces an approximation of what the human eye would see, and even then there's the issue I mentioned above of colour fidelity in the entire capture, processing, and reproduction chain). It also may use non-visible light, such as infrared. Pointing it at a screen or other reproduction is basically a non-starter.

Offline bknight

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Re: Getaway special for 9-11 conspiracy theorists
« Reply #61 on: August 02, 2015, 08:38:39 PM »
Actually I was referring to videos, not film.  It seemed likely that the color signature would be recorded and then be able to analyze the spectrum.  But if you guys don't think it would work, ok by me.
Truth needs no defense.  Nobody can take those footsteps I made on the surface of the moon away from me.
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Offline Abaddon

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Re: Getaway special for 9-11 conspiracy theorists
« Reply #62 on: August 02, 2015, 11:12:34 PM »
Actually I was referring to videos, not film.  It seemed likely that the color signature would be recorded and then be able to analyze the spectrum.  But if you guys don't think it would work, ok by me.
Same argument applies. The video recording device, codecs applied and screen reproducing the video will not accurately reproduce anything spectrographic.

Offline ka9q

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Re: Getaway special for 9-11 conspiracy theorists
« Reply #63 on: August 03, 2015, 04:22:30 AM »
Actually I was referring to videos, not film.  It seemed likely that the color signature would be recorded and then be able to analyze the spectrum.  But if you guys don't think it would work, ok by me.
A spectrometer looks for lots of discrete wavelengths characteristic of specific materials. Film or a color TV camera can be thought of as a spectrometer, but one that (like the eye) looks only at three very broad spectral ranges (red, green, blue). In some cases this might be enough to identify a material, but certainly not in general. Consider how hard it can often be to distinguish brass from bronze from gold just by eye.