Purpose
Given the pixel coordinates of an object on a red LRIS image,
compute and apply the required telescope move to bring the
object to the center of the LRIS 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 red detector center
centr 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
centr -n 100 200