Colour Banding Test

In short Banding is when a smooth gradient breaks into visible steps instead of a continuous blend, and a little of it is normal. Most laptop screens and budget monitors are 6-bit panels using frame rate control to approximate 8-bit, which produces mild stepping that is visible on a test pattern and rarely noticeable in real content. Heavy, obvious banding on a panel sold as 8-bit or 10-bit is a different matter. Before concluding the panel is at fault, check the signal chain, because the commonest cause is not the display at all. If it looks worse in your browser than in a photo viewer, that usually points at the graphics driver — often a limited RGB range being sent to a monitor expecting full range, which compresses the tonal range and produces exactly this. On Nvidia and AMD control panels the setting is Output Dynamic Range or RGB Range, and setting it to Full frequently removes banding people had blamed on the screen for months.