Quote:
Originally Posted by etype2
The field sequential system could have been viable and had advantages. Simple tube, less parts, no convergence requirements, brighter images, higher resolution, no dot or stripe deposits required, no moire effects.
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The field sequential system had advantages as originally demo'd vs. simultaneous sustems as originally demo'd, but it had disadvantages too that weren't often mentioned.
It could have convergence problems if the high voltage wasn't well filtered, or the B+ had a little hum that modulated the scan differently in each field.
The camera had hue shift due to partial image retention from one field to the next. The color filters in the camera and receiver could be chosen to compensate this, but if the characteristics of either were changed in the future (maybe for optical efficiency) there might be hue shifts with no customer hue control to fix it. CBS did tests with non-expert viewers to determine which way the hue error was likely to be least noticeable (RGB sequence or RBG - they chose the latter).
On the face of it, you would think the simpler camera optics would make it more sensitive than a three-tube TK-41, but the less than ideal filters combined with a shorter field exposure time took away that advantage.
The basic flicker rate in the display was the same as double-shuttered movies - 48 Hz. While the maximum flicker modulation only occured for pure green, this was still approaching the 50 Hz flicker rate of European systems, and was a step backwards for 60 Hz countries in terms of the picture brightness that ultimately could be used. Note that much later sequential displays (single chip DLPs) for HD projectors always use much higher field/frame rates. Looking at the 10-inch SD monitors at the Early Television Museum, you can verify that the color breakup is practically unnoticeable and flicker is not visible, but this is not the case for a large, bright high-definition display.
The bottom line is, you don't get something for nothing - physics and psychophysics both giveth and taketh away.