Enter test screens, the digital color swatches that you can use to dial in your color settings (such as the hue, saturation, contrast, and temperature).

The test patterns can be downloaded from the AVFoundation page on Apple's website under Related Resources > Color Test Patterns, with complete instructions available in Apple's support document.

Taking the test is easy. Head over to the website where you’ll be prompted to select the color blue or green (whichever you think the shade looks like to you). The hues on the screen change from ...