Color

DS9  supports a number of color environments. Not all color environments, or visuals, are available on most machines. In fact, you may be restricted to one or two, base on the color graphics hardware your computer has. A color visual is composed of two parts, the color model and the bit depth. Pseudocolor uses a color lookup table to derive the correct color, Truecolor uses the value directly as a RGB triplet, to derive the correct color. The follow is a list of the color visuals DS9 currently supports:

pseudocolor, 8 bit

truecolor, 8 bit

truecolor, 15 bit

truecolor, 16 bit

truecolor, 24 bit

You can use the xdpyinfo command to see if one of these visual are available. NOTE: Linux Users-- if your desired visual is not available, use the Xconfigarator command  (Red Hat) or similar command under other versions of linux, to configure your X window visuals.

When DS9 is invoked, by default, it will use the default visual. You can find out what the default visual is by using the xdpyinfo command. You can also force DS9 to use another visual by command line option. If you specify a visual, and it is not available, DS9 will exit with an error message.
 

$ds9                      # default visual, default depth
$ds9 -visual pseudo       # pseudocolor, default depth
$ds9 -visual pseudocolor  # pseudocolor, default depth
$ds9 -visual pseudocolor8 # pseudocolor 8
$ds9 -visual true         # truecolor, default depth
$ds9 -visual truecolor    # truecolor, default depth
$ds9 -visual truecolor8   # truecolor 8
$ds9 -visual truecolor16  # truecolor 16
$ds9 -visual truecolor24  # truecolor 24