Drawing Mode

Select the mode which controls the interaction of the color "pen" and the image on the screen.

Line Width

Specify the line width in units of screen pixels.

Marker Size

This general feature is disabled for line profile plots.

Hit Radius

Specify the radius in screen pixels in which the mouse arrow is is deemed to have hit a drawn line. This is used for highlighting the line in Move mode.

Click this button to open a Color Picker dialog for choosing the color of the lines.

Opens a Font dialog for choosing the font for drawing the line text.

 Centroid First Point

Check this box to make the line begin at a centroid coordinate calculated near the point where the mouse started the line.

 Centroid Last Point

Check this box to make the line end at a centroid coordinate calculated near the point where the mouse ended the line.

Centroid direction:

These bullets control the assumption about the value of feature relative to the background. Usually, the centroid is done on positive (bright) features or points.

 Positive: The centroid is computed for a source brighter than the background.

 Negative: The centroid is computed for a source darker than the background.

Sample Radius

Specifies the radius over which the centroid calculation samples the pixel data for intensity information.

 Track Centroid

This general feature is disabled for line profile plots.

 Track Centroid Endpoint

This general feature is disabled for line profile plots.

 Centroid after Move

This general feature is disabled for line profile plots.

Search Radius

This general feature is disabled for line profile plots.