The background of the Chimera graphics window can be set to a single solid color, a vertical gradient of multiple colors, or an image read from a file. These and related parameters can be controlled with the command background or in the Background section of the preferences.

Gradients may contain any number of colors, and can be shown as discrete bands or interpolated in the RBG or HLS color space; they can be created, previewed, and named using the Palette Editor. Background images can be cropped, stretched, centered, or tiled. Image formats include PNG, TIFF, and JPEG.

The image shows the structure of the human OX2 orexin receptor bound to the insomnia drug suvorexant, Protein Data Bank entry 4s0v. The drug is shown as spheres colored by element, and the receptor as ribbons with secondary structure elements rainbow-colored from blue at the N-terminus to red at the C-terminus. (More samples...)