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Quoth · 12-19-2023, 05:03 PM

Colour TV (and most digital video) is still less than mono resolution. For analogue about 1/4 horizontal and on some systems 1/2 vertical. VHS is about 1/6th to 1/8th horizontal colour resolution. The mono resolution was unaffected. With digital there is less data used for the colouring information than the monochrome image. See https://en.wikipedia.org/wiki/Chroma_subsampling#4:2:2

But colour LCD and colour eink work differently for lighting. The mono display panel (either LCD or eink) has a coloured filter, so the mono resolution is also lowered. An LCD or eink 1920 x 1080 coloured panel is using either 5760 x 1080 mono cells or 3840 x 2160 mono cells, depending on if it's stripes or a 2 x 2 pattern. There are other filters.
LCD is back lit so the light is attenuated once by the the filter, and the light is simply made brighter. The eink is front lit so the filter reduces the brightness of the daylight or the front light twice.

So colour eink is inherently darker and lower resolution than the equivalent mono panel with no filter. They changed from more saturated colours (Triton) to pastel shades (Kaleido) to brighten it a little, on the basis that there are so few grey levels (14 + black + white) that the colour is rubbish anyway compared to LCD, CRT, OLED or QLED (actually LCD with a blue backlight and only "quantum" dots for green and red, that change the blue instead of filter "white" light).

12-19-2023, 05:03 PM	#7
Quoth the rook, bossing Never. Posts: 11,609 Karma: 87456643 Join Date: Jun 2017 Location: Ireland Device: All 4 Kinds: epub eink, Kindle, android eink, NxtPaper11	Colour TV (and most digital video) is still less than mono resolution. For analogue about 1/4 horizontal and on some systems 1/2 vertical. VHS is about 1/6th to 1/8th horizontal colour resolution. The mono resolution was unaffected. With digital there is less data used for the colouring information than the monochrome image. See https://en.wikipedia.org/wiki/Chroma_subsampling#4:2:2 But colour LCD and colour eink work differently for lighting. The mono display panel (either LCD or eink) has a coloured filter, so the mono resolution is also lowered. An LCD or eink 1920 x 1080 coloured panel is using either 5760 x 1080 mono cells or 3840 x 2160 mono cells, depending on if it's stripes or a 2 x 2 pattern. There are other filters. LCD is back lit so the light is attenuated once by the the filter, and the light is simply made brighter. The eink is front lit so the filter reduces the brightness of the daylight or the front light twice. So colour eink is inherently darker and lower resolution than the equivalent mono panel with no filter. They changed from more saturated colours (Triton) to pastel shades (Kaleido) to brighten it a little, on the basis that there are so few grey levels (14 + black + white) that the colour is rubbish anyway compared to LCD, CRT, OLED or QLED (actually LCD with a blue backlight and only "quantum" dots for green and red, that change the blue instead of filter "white" light). Last edited by Quoth; 12-19-2023 at 05:06 PM.