CHANGE_NACENTRE - Shift the Nasmyth centre of the array

Description:

This routine shifts the position of the Nasmyth centre of a SCUBA array. It can be used to take out the small difference between the centres of the LONG and SHORT wave arrays. Should be run after extinction.

Usage:

change_nacentre [-h $\vert$ -v] infile dx dy

Parameters:

$-$h

Return a help message only.

$-$v

Return the version number of scunoise

infile

Input file name. The file is modified in place.

dx

Shift in Nasmyth X (du3) direction

dy

Shift in Nasmyth Y (du4) direction

Examples:

change_nacentre

Will prompt for input file name and shift

change_nacentre file 5 $-3$

Will move the array centre of file.sdf by (5,$-3$) arcsec.

Notes:

This command can only be reversed by running change_nacentre with minus the previous X,Y shift. extinction must have been run on the input file (otherwise the file will contain more than 1 array) - this is not checked for explicitly.

Related Applications

SURF: rebin