World Coordinate Systems in SAOimage

Five WCS modes

27 proposed FITS standard WCS types

Digital Sky Survey plate solutions

approximate plate-tangent WCS given a plate center and scale

IRAF TNX polynomial projection.

SAO polynomial projection.

Keyboard and Cursor Commands

Command Line Options

Multiple WCS Support

Examples

Example 1. Append the WCS position for the current cursor location to a file
Example 2. Use sgsc to identify the closest HST Guide Star
Example 3. Find an image star in various catalogs.
Example 4. Use imcat to display catalog stars on an image with a WCS.

Setting an Image WCS

imwcs has been developed to set the WCS of an image by matching stars images to a catalog, such as the HST Guide Star Catalog or the USNO A 1.0 Catalog, with no user interaction.

Subroutines

The subroutine library, libwcs, used by SAOimage is available for inclusion in other programs.