Regions

Source/Background

The Source/Background properties flag the region for use with other analysis applications. The default is source
Example: circle(100,100,20) # source
         circle(200,200,10) # background

Fixed in Size

Composite Region

A Composite Region is a region which is a collection of other regions, which share common properties. A composite region is composed of a center point and a rotation angle, of which all its members are rendered in reference to. A composite region is defined by the # composite x y angle declaration followed by a number of regions who are or'd together. A composite region is manipulated as a single region within ds9. A composite region maybe created from the current selection of regions by selecting the Create Composite Region menu option. Likewise, a composite region can be desolved by selecting the Desolve Composite Region menu option.

Template Region

A Template Region is a special form of a region which is saved in a special wcs coordinate system WCS0. WCS0 indicates that the ra and dec values are relative to the current WCS location, not absolute. A template region can be loaded at any location into any fits image which contains a valid wcs. For example, a user may create a series of regions, which represent an instrument template. Then, by selecting the Save As Template menu option, a template region saved. The user may now load this templated into any other fits image which contains a valid WCS.