Quote:
Originally Posted by yagosaga
You have to adjust a correct contrast-rich black and white picture before you add color.
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Hi Eckhard,
I agree the contrast range must be ideal before color is added; so I went back to my library of shots, ones taken 12-28-2007, and selected this example of contrast range. This remember was taken before the set was calibrated and so the colors are imperfect. However, note the range of brightness from white (that little wedge showing but mostly masked by the roundy CRT) down 8 steps to black. This test signal remember is from the DVE test disk -- it was made for modern digital sets, and the CT-100 displays it perfectly. It seems also that the A630-camera-to-monitor link displays an analog of that CT-100 screen fairly well. So, based upon this and other examples, I suspect the contrast range of this CT-100 is correct.
Keep in mind that the CT-100 was designed to display the 1953 NTSC standard. It may be the only consumer set that could (at least up until today's wide color LCD LED sets, and with those I wonder if they can actually display a full analog NTSC signal or just do the wide color space through a digital interface like HDMI).
I believe the CT-100 will reproduce the full contrast range, decode the full chroma signal in a wide-as-possible bandwidth (ameliorated by issues with the quadrature encoding-decoding scheme), process that decoded chroma in a 1953-correct NTSC matrix, and display the resulting RGB signal with 1953 NTSC spec phosphors. I don't know if anything other than a true clone of the CT-100 can do those things.
A word about calibrating the CT-100. My method or methods for adjusting a CT-100 come from multiple sources (oh to be able to watch the CT-100 techs setting up these sets coming off the line). The well known SAMS and other sources are basically derivatives of RCA material. But fortunately, one of the Zenith engineers deeply involved with color set design back in 1953 casually related a bit of kernel information that promotes linear operation of the video circuitry (an advance rather than retard thing when setting the screen controls early in the setup procedure). A luckly bit of history available today.
Pete