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Old 02-04-2010, 04:16 PM
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old_tv_nut old_tv_nut is offline
See yourself on Color TV!
 
Join Date: Jul 2004
Location: Rancho Sahuarita
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This is the first time I've compared the spectra on that CRT spec to the NTSC standard - I always asumed it matched - but it appears that the red and blue are both more extreme than the NTSC standard says they should be. This needs further study.

LED red and traffic signal red made with an incandescent lamp and red filter are both outside the NTSC standard gamut and outside every color TV gamut proposed since. Auto tail lights, however, are quite orangy and are inside the gamut.

The NTSC standard blue is much less violet than modern tubes' blue or SECAM or HDTV blue. The reason is that they had trouble at first making the modern sort of blue because even a small amount of contamination would turn the blue phosphor to green. Therefore, they went to a less-violet blue formulation that did not suffer from contamination. Once the contamination problem was solved, it was possible to build the all-sulfide tubes, which moved blue towards the modern deep blue, but also moved the green forever towards yellow.

Regarding the parrot and color bars images: the mechanical TV pictures (at least as photographed) have a very strong highlight white balance towards purple. No attempt should be made to judge the colors relative to the CRT until this problem is fixed.
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