Purpose
Given the pixel coordinates of an object on an offset guider image,
compute and apply the required telescope move to bring the
object to the center of the offset guider detector.
Usage
gcent [-n] x y
Arguments
-n = no move, only print the required shift
x = column location of object [pixels]
y = row location of object [pixels]
Output
Exit values
0 = normal completion
1 = wrong number of arguments
Example
1) Move a target at pixel (100,200) to the detector center
gocent 100 200
2) Display the telescope move required to shift a target at
pixel (100,200) to the red detector center without moving the telecope
gocent -n 100 200