Color Depth

You can create bitmaps with the following number of colors:

32bit alpha channel

CMYK (TIFF files only)

24 bit Millions of colors

8 bit 256 colors

4 bit 16 colors

1 bit 2 colors

Many bitmap formats support only some of these color options. For example, the GIF format supports 256, 16 or 2 colors. Other options are dimmed.