Glossary A–ZLetter G
Greyscale levels
Greyscale levels state how many brightness steps a screen can use to display each primary colour.
For LED walls, the value is usually given in bits. 14 bits, for example, stands for 16,384 steps per colour.
The more steps are available, the smoother colour gradients look, such as a sky or a shadow. On LED walls the value is particularly important because they are often run heavily dimmed, for example in the evening or indoors. Dimming loses steps: a wall running at only part of its brightness also uses only part of its gradations. Visible banding and colour casts then appear in dark areas.
The figure in the data sheet often refers to full brightness; more telling is how the wall looks at the brightness actually used. Greyscale is closely linked to the refresh rate and the controller and cannot be increased independently of them. Before buying, operators should ask for a demonstration of the wall with dark gradients and at the planned brightness.