Quote:
Originally Posted by etype2
Was there ever any 1953 NTSC color consumer or professional content based on the true NTSC Color Gamut and if so, are there photographs displaying the wide color gamut on a CRT?
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I'm not sure what you mean by consumer content. In 1953 only professional cameras were available.
The original RCA TK-41 cameras were designed to come as close as possible to correct for driving a display with NTSC phosphors. Calculations based on spectral sensitivity measurements (rescued from loss at RCA) show this.
http://www.bretl.com/viewing1950scolor.htm
This was achieved with narrow-band optical filters and no electrical matrixing, as that would have brought on increased noise and stability problems. The result is that very slight adjustments in the color level and hue settings of a receiver/monitor would produce excellent color matches for common surface colors, better than any photographic film. However, the cameras also had less gamma correction than required to match the CRT gamma, resulting in increased contrast and color saturation. The cameras thus had a problem of limited dynamic range (as did the CRTs if viewed in a lighted room). The system was similar to Technicolor film in this regard, requiring reduced lighting ratios, substitution of grayed or light blue shirts for white, etc., along with very careful exposure adjustment to put the subjects in the middle of the gray scale.
Later cameras with less noisy pickup tubes and wider bandwidth color optics used electrical matrixing, but it was still set to NTSC specs at first. Meanwhile, display makers had adopted non-standard phosphors and electrical matrixing to keep the hue spread proper between red, yellow and green (and fleshtone). And while camera makers kept the matrix for NTSC at first, they also played with the color separation optics to get the best looking color on monitors, and eventually fudged things entirely to look good on more modern monitors, which had the new phosphors, but a matrix on/off switch. Which position of the switch was the camera fudged for? No one knows what a particular brand of camera did anymore, and it may have been a compromise. One of the glaring problems with the receiver/monitor matrix is that it exaggerated the brightness of reds and reduced subtle variations in them.
All the above mess happened with NTSC. With PAL, because it was established after the new phosphors were usual, the PAL camera optics and matrix was specified to get a proper match without the approximate electrical matrix in the receiver. This practice was incorporated in HDTV and the sRGB still picture standard for computers.
If your question is, is there any material available now that you could play on an early set with NTSC phosphors and know you are seeing NTSC color, the answer in some cases is probably not, and in other cases definitely not. You often can see the high contrast and noise of TK-41s in DVDs of old shows from the early 60s or earlier, but the color may or may not reflect the TK-41s accurately, depending on how much color correction was done in remastering, which of course would have been judged on a modern monitor.
Any of our favorite DVD or Blu-Ray movies for demonstrating old sets are far removed from NTSC. You may see the brilliant emerald greens, but there is no way of knowing if they are correct, because these have all been remastered for current receivers/monitors.
Quote:
Originally Posted by etype2
... are there photographs displaying the wide color gamut on a CRT?
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No.
Color film could not reproduce the NTSC green. Modern monitors cannot reproduce it, and therefore digital photos generally do not reproduce it. As stated above, it is outside the sRGB color space. Thus, when you post jpg files to the web, the viewers really can't see an accurate reproduction of what you had on your NTSC screen.
If you put color bars on your old set, take a picture with a digital camera set to Adobe RGB or prophoto RGB, and display it on a wide-gamut monitor (or the old TV), then you should see the NTSC primaries and secondaries reproduced, sort of. There are many caveats about how the raw data is processed by the digital camera or raw-file processing program, all of which are fudged to get a preferred film-like reproduction rather than a colorimetrically accurate one. Still camera makers and Adobe tumbled to the fact that a film-like "S-curve" contrast response is greatly preferred over the older video camera gamma curve that clipped overexposed highlights.
What to do? Turn on your set, play whatever you like, adjust for best looking results, and enjoy.
I haven't looked lately to see if Photoshop and Lightroom have an NTSC monitor profile available, but if they do and you have an NTSC composite output on your computer, you could display stills from raw files that are close to correct. Failing that, Adobe RGB profile would be close in the reds and greens, but not so great in the blues.