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True! You’re less likely to be surprised by banding on a display, because you can see it before it’s a problem, and it’s less likely to cost money, but for sure the need for dithering is still there, especially for displays that can do more than 8 bits per channel or can do high dynamic range.

> Consider that a grayscale gradient can only have 256 distinct levels.

This is true, but also keep in mind that for print and low dynamic range displays we humans only need approximately 256 levels, as long as the levels are perceptually spaced out evenly. 8 gamma corrected bits per channel actually made sense for a long time, for both print and for TVs & monitors, until HDR displays came along, relatively recently. Needing dithering for 8 bit images displayed on a 10 bit display is perhaps less surprising than needing dithering even when your display and your printer are both only 8 bits, right?

by adgjlsfhk16 hours ago|

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I think HDR wasn't what changed. It's resolution. At 720P and below, you don't notice dither because pixelation is the more obvious problem. Once you're at 1080p (and it's more obvious at 1440p/4k), you start having enough detail to see the banding patterns.

by dahart6 hours ago|

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I don’t think I agree with that at all. Color banding is a problem with NTSC - 540 interlaced, and lower resolutions too. If you have a smooth gradient that shows color banding, spatial resolution is completely irrelevant. Pixelation is a separate, orthogonal issue. It would be trivial to show color banding, and the need for dither, on a 16 x 16 pixel image.

HDR is what changed - it requires more than 8 bits per pixel, by definition!

Again, if you only have LDR (low dynamic range), the human visual system’s “just noticeable difference” or JND in the perception literature demonstrates we only need 8 bits when looking at things under ‘indoor’ lighting conditions. You don’t need dithering if you use LDR on a single specific 8-bit display. You do need dithering when either moving to a different display than the one you started with, or using an HDR display - capable of displaying more than 8 bits of color resolution.