Rainbow Test
A moving black-and-white grid that shows the rainbow effect on single-chip DLP projectors.
How to use it
Show this page on the projector from a PC or media player, full screen, at native resolution. Watch the moving lines, and let your eyes dart across the screen too. A single-chip DLP shows the colours one after another, so a white line can split into red, green and blue. The faster it moves, the wider the split. A projector with a faster colour sequence (an anti-RBE mode, for example) shows less of it at the same speed.
Line colour
White is the main test: a white line is lit in every colour field, so it gives the strongest rainbow. Coloured lines are only for diagnostics. In a pure RGB mode, pure red, green and blue should show little or no rainbow, because each one is lit only in its own field. If they show a clear one, the mode is mixing colours (adding cyan and yellow fields, for example). A faint rainbow is possible even in a pure RGB mode if the projector blends in other colours to hit the Rec.709 gamut. Yellow, cyan and magenta split into their two components.
Mouse: click the grid to pause, double-click for fullscreen. Keys: arrows — direction, + / − — speed, space — pause, F — fullscreen.