SAOimage (pronounced S-A-0-image) is a utility for displaying astronomical
images in the X11 window environment. It was written at the Smithsonian
Astrophysical Observatory by Mike Van Hilst in 1990 and is now maintained
by Doug Mink.
Image files can be read directly, or image data may be passed through a
named pipe (Unix) or a mailbox (VMS) from IRAF display tasks. SAOimage
provides a large selection of options for zooming, panning, scaling,
coloring, pixel readback, display blinking, and region specification.
User interactions are generally performed with the mouse. Mouse tracking in
an image's world coordinate system, usually sky coordinates, was added in
1994. You can also plot catalogs over images with WCS information in their
The SAOimage desktop includes, a main image display window, a button menu
panel, a display magnifier, a pan and zoom reference image, and a color bar.
A color table graph window can be brought up by clicking on the color bar.