Point Marker Properties

 Mark Centroid

Choose whether to locate the objects at a refined centroid position rather than the exact point where you click.

 Positive

If marking the centroid position, the centroid is computed under the assumption that objects have positive brightness above the background level.

 Negative

If marking the centroid position, the centroid is computed under the assumption that objects have negative brightness below the background level.

Radius

Defines the distance from the target point within which pixel data are used to compute the centroid position. A reasonable starting point for choosing a value is 2 times the FWHM.

(Note: FWHM measures a diameter and this parameter is a radius).

Tracking

Defines the maximum distance from the current position that Mira will search in the next image to lock onto a new position. This is only used when tracking objects through an Image Set.

 Track Centroids

Controls the duplication of markers when the positions are "tracked" through an image set. If this option is checked, the positions are centroided in every image.

 Calibrate when Tracking

Instructs Mira to compute and apply the zero point to all objects when tracking through an image set. This is a time saving feature that makes it unnecessary to follow Tracking by Calibration as a separate step.

Object Color

Selects the color used for object markers.

Standard Color

Selects the color used for standard star markers.

Import Catalog

Imports and processes a catalog containing coordinate and photometric data from a text file as an alternative to marking points manually. See theImport Photometry Catalog tool.

Reset Zero Point

Resets the photometric zero point value.

Recenter All

Re centers the marked objects, usually done after changing the marker centroid properties (see above).