Banding is when a smooth gradient, a sky or a dark film scene, breaks into visible stripes. Here the ramps come first: gray, then red, green and blue, then a stretched shadow ramp. The black-level and gamma steps follow, because crushed levels and banding usually share a cause, and the color swatches close the run.
Press Start full-screen test and step with Space or →.
What the ramps are
The ramps are drawn on a canvas, pixel for pixel, with every level from 0 to 255 as its own band and no smoothing. The HTML standard sets a canvas to 8 bits per channel unless a page asks otherwise, so this is the full 8-bit range: about 16.7 million colors across the three channels. A 10-bit signal has 1,024 levels per channel, and no web page can show that difference reliably, so this test doesn’t claim to.
What the ramps do show is whether the 256 levels survive the trip through your graphics settings and your screen. Every level should look a little lighter than the one before it.
How to read them
- Gray ramp: fine, evenly spaced steps are normal. Wide stripes, a step that jumps, or a section with a color tint point to levels being merged or a color profile at work.
- Red, green and blue ramps: each should stay its own color from dark to full. A ramp that turns muddy or jumps in one channel only points to a calibration or profile problem.
- Dark ramp: levels 0 to 48 stretched over the whole width, where shadows band in films and games. If the first several bands merge into black, look at the black-level test next.
Common fixes
Turn off dynamic contrast, “black enhancers” and sharpness boosts, and try the screen’s standard or sRGB mode. On a PC, check that the graphics driver’s output range matches the screen: a full-range (0–255) signal on a screen set to limited range merges the darkest and brightest levels into black and white, and the reverse turns black gray and whites dull. Many panels show extra shades with Frame Rate Control, which BenQ describes as pixels flashing between two colors; it is normal and you won’t see it on a static ramp.
The refresh rate test covers motion, and the full monitor test runs all nine checks.