gstar2

Much like gstar, but with extra options. As of Aug2016, the extra options are explained with the dedicated script "gstar2_explain". If you type "gstar2" with no arguments, then gstar2_explain is called and the full set of explanations is presented along with the usual usage message. If this seems klugy, it is! During the HET upgrade commissioning there was a fairly steady stream of "can it do this?" requests. Instead of trying to alter a code that was in very regular use (gstar) we chose to build a new script with experimental fatures (gstar2). Frankly, I am surprised that as late as Aug2016 this routine still uns!. 


% gstar2 
	 **** Extra notes on gstar2 ****

Usage: gstar2 06:15:20.46 +39:51:50.6 304.0 gc2
arg1 - RA  (sexigecimal)
arg2 - DEC (sexigecimal)
arg3 - Azimuth of HET structure (degrees)
arg4 - probe name 

NOTE:
You can make a local file named Offset.Angle that contains
an offset rotation angle in degrees (0.5).

You can make a local file named IHMP.Position that contains
the X,Y of the IHMP in ACAM pixel coordinates (e.g. X,Y=174,382).

You can make a local Probes.Current to specify the probe 
positions for gc1,gc2,wf1,wf2.

You can make a local Probes.Scale_Factor to change the probe 
positions by a fixed scale factor (i.e. 1.000123).

You can make a local IFU.Recenter file with the name of the  
IFUSLOT (i.e. 053) that you want to center on.
Most often gsstar2 is used to recenter a target in a specific IFUSLOT position. The position must be listed in the Active.IFU file (see below) before it can be recognized and used in gstar2. 

IFU must be listed in the Active.IFU list (Only SCO):
% cd $VIRDAT 
% vi Active.IFU

To run for a specific IFU, create a local file = IFU.Recenter
% cat IFU.Recenter
053
Run code in the usual way, and the routine will tell you the new gstar command line you must run to recenter for the IFU desired. 

Example: 
% gstar2 06:15:20.46 +39:51:50.6 304.0 gc2

**** The usual message and ds9 window appear ****, then 

Mark desired guide star for gc2 with GREEN CIRCLE,
OR, 
Mark new IHMP position with MAGENTA CIRCLE,
OR, 
Mark shift with a VECTOR,

Then hit any KEY. (S to stop cleanly  now):

	Recenter IFU 053 to Ra,Dec = 06:15:17.197 +39:57:42.14

The new RA,DEc will be:   06:15:23.7202 +39:45:59.079

Make a new gstar2 run with: gstar2 06:15:23.7202 +39:45:59.079 304.0 gc2 None
When the "IFU.Recenter" is not present, then the user is presuambly going to use one of the three interactive options listed above:
  1. Use a green circle to mark a guide star.
  2. Use a magenta circle to mark directly a new IHMP position.
  3. Use a cector marker to indicate position shift on the sky.


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