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Old 03-20-2017, 06:20 PM
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Somewhat off the 80's ENG topic, but may be some indication of the question about color differences:

When we did the format comparison tests for setting the HDTV standard in the early 90s, the HD cameras all used Sony Saticon tubes. However, Sony would not make any versions with scan rates other than 1125 interlaced; the others were done with a BTS camera with interchangeable scan rates up to 1050 interlaced and a specially modified BTS camera to do 787.5 progressive (Zenith's proposal). Sony sold the Saticons to BTS, but would not sell their proprietary low-noise pre-amps, so BTS had to unsolder the preamp from the tube face, return it to Sony, and solder on their own preamp.

Regarding color, the Sony camera was unique, and had a matrix that did not match the HD standard at all - it had a unique Sony look. IIRC, the yellows were super-bright compared to the real world, and actually ended up outside the HDTV gamut, although they really were not that way on the chart.

LeRoy Demarsh of Kodak and others including me did measurements on the Macbeth color chart for all the cameras and calculated the best (least mean square error) color matrix for each. It turned out that the BTS cameras were already close to proper. In fact, they may have been precisely correct theoretically, but it was hard to tell, as the Saticons had a positive but temporary image burn in, that is, the brighter patches got even brighter over the first 5 minutes or so of staring at the pattern, so a red patch got even redder, a blue patch got bluer, etc. This meant that our scope measurements depended somewhat on which order we measured the patches in. The Sony had to be modified to give standard color reproduction, so that the subjective comparisons of resolution (done by non-expert viewers) would not be confused by differences in color.

So, this makes me think the observations above about color oddities may have something to do with a unique "Sony look."
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