Build a simulated ACAM image that has WCS in the FITS header for a given Ra,Dec,AZ of the HET.

 
% acam_fake 23:57:24.01 +61:07:35.8 336.0 178.0 391.0 Y  

Usage: acam_fake 23:57:24.01 +61:07:35.8 336.0 178.0 391.0 Y
arg1 - RA  (sexigecimal)
arg2 - DEC (sexigecimal)
arg3 - Azimuth of HET structure (degrees)
arg4 - X_ihmp 
arg5 - Y_ihmp 
arg6 - Display with ds9 (Y/N) 
Note for ihmp: X,Y= 173 394; later X,Y= 178 391 

Sometimes, I might want to build the image, but then not have the automatic ds9 display stuff activated. I could turn the ds9 option off (arg6=N) and then display things manually with:

 
% acam_fake 23:57:23.97 +61:07:37.4 336.0 178 391 N 
% ds9_open 1000 1000 
% xpaset -p ds9 file dss.fits 
% xpaset -p ds9 scale limits 0.0 20000.0 
% wcs_outline acam_dss.fits dss.fits 
% xpaset -p ds9 zoom to fit 
% cat STARS.cdfp.reg | xpaset ds9 regions -format ds9 

The acam field overlaps the LRS Red and Blue IFU slots.

 
From the Nov2015 run we measure ACAM positions for LRS2:
    LRS2_RED    730  585
    LRS2_BLUE   738  217

The IHMP position at that time was assumed to be: X=178 Y=391

 
%  gstar 06:15:20.46 +39:51:50.6 304.0 gc1 

There is a bright star that I want to go into LRS2_RED:
Ra,Dec = 06:15:17.075 +39:56:45.60
The AZ would remain the same (304). So I would run:

font color=black size=5> 
% acam_fake 06:15:17.075 +39:56:45.60 304.0 730.0 585.0 N

 
font color=black size=5> 
Assume IHMP X,Y = 178,391 

% xy2sky acam_dss.fits 178 391 
06:15:03.763 +39:56:06.63 J2000 178.000   391.000

This means I want to run gstar with: Ra,Dec = 06:15:03.763 +39:56:06.63
To be sure I use the proper X,Y_IHMP:
% cat IHMP.Position 
178.000   391.000

%  gstar 06:15:03.763 +39:56:06.63 304.0 gc1  
 

A sample gstar image for setting up the LRS2 R channel onto a bright star. After the initial image is made, we are ready to select a guide star.

Here I describe a full example of observing a well known galaxy.

 
% rc3gal n205 
Name_RC3      RA_2000DEC_2000    Type     Input_name
NGC   205    00:40:22.50 +41:41:11.0  .E.5.P.   n205      
dssget  10.093751  41.686390 10.0 dss poss1_red

% skycal.sh 00:40:22.50 +41:41:11.0 now 
From the listing: 
Summary of SKYCAL data: 
Target RA,DEC                          : 00:40:22.50 +41:41:11.0
UT date                                : 20160210
UT                                     : 23:43:34
LST                                    : 02:09:27.19
Hour Angle                             : 01:29:04.69   (WEST)
Target Altitude,Azimuth (degrees)      :    69.011   307.804
Target airmass                         :   1.071

To get the AZ I would use with the HET:
Usage: estimate_azhet_hetq 02:35:27.90 +39:39:52.0 63
arg1 - RA in sexigecimal format (hh:mm:ss.ss)
arg2 - DEC in sexigecimal format (+dd:mm:ss.s)
arg3 - approximate AZ

% estimate_azhet_hetq 00:40:22.50 +41:41:11.0 307.8 
300.070  274.68338

% cat estimate_azhet_hetq.explain
AZ HET_PA
AZ     = HET structure azimuth 
HET_PA = HET parallactic angle 

To get the acam image:
% acam_fake 00:40:22.50 +41:41:11.0 300.07 730.0 585.0 N
% xy2sky acam_dss.fits 178 391 
00:40:08.691 +41:40:38.97 J2000 178.000   391.000
%  gstar 00:40:08.691 +41:40:38.97 300.07 gc1  

For gc1 star, use x_ang,y_ang = 0.06513 -0.14562
 
Ra,Dec,Az(IHMP):
 00:40:08.691 +41:40:38.97 300.07 
Telecen_X, Telecen_Y, (Ra,Dec)_probe, Probe_name: 
 0.06513 -0.14562 00:40:57.867 +41:43:52.38 gc1 
syscmd -T -v 'Guider1_set_position( x_ang=0.06513, y_ang=-0.14562) '
syscmd -T -v 'pfip_move_probes()'
*** These Telecen_X,Y have tested as VALID 

The gsatr result our effort to place the galaxy NGC205 onto LRS2 R. We use a simple run (rc3gal) to find the coordinates for this famous galaxy. We make the "fake" acam image in order to learn where our IHMP center must fall on the sky. We use a few little scripts to learn the azimuthn we'll observe at, and then we run gstar to verify that NGC205 will fall inthe correct IFU and to select a guide star for gc1.

Hi Matt (and Gary):
  I was thinking about our conversation last night on how to establish 
the X,Y coordinates of points in the IHMP system (i.e. the x,y for 056,
066,555 etc in the fplane.txt file.)  You said you were going to play 
around with Steven's images used to establish the acam positions for 
these things. These questions are critical for how we do blind setups, 
so they are worth considering. 

 I'm prety sure we really have two problems at play here:
    1) how to we predict x,y of targets in the simulated 
       acam image (whether by shufle or other codes) 
    2) How we predict where an ihmp position is on the acam

The job of #1 is performed (in shuffle, fake_acam, etc...) with 
four numbers:  the acam position of the ihmp center (in shuffle 
these are acam_x_origin,acam_y_origin), the small change to the 
general field rotation beyond that predicted by the parallactic 
angle (in shuffle this is the variable named "acam"), and the 
plate scale (not sure what this is called in shuffle, but we know 
it is PS_acm = 0.2709 -+0.0002 arcsec/pixel). 

**** I think these are the ONLY 4 numbers (3 really) that you 
     should adjut. Not any ihmp x,y values. 

The point is that we need to be able, via those four numbers, make 
any real X,Y of a target in the acm match the shuffle value. ANY  
acm image with a suffient number of stars can be used for checking 
this. I have 90 acm images (since Dec2017) that are well calibrated 
(WCS with 0.2" to 0.4" rms) and a list of dates when ihmp or fpa 
work was done.  I'll be looking into how well we can predict the 
(X,Y)_acm for all targets in the field.  In other words: I'll use a 
large number of acm images to determine the 4 shuffle parametrs. 

  The next part (#2) is a separate problem. How do we take X,Y_ihmp 
(fplane.txt coordinates) and predict positions in the acm coordinate 
frame. The bottom line is: we shoyld not be changing shuffle parameters 
AND fplane.txt position with the same data sets. 

  The question is how we determine firm ihmp positions. With regard to 
ihmp positions, I see a way forward with the LRS2-R,B.  However, I'm 
really wondering how the fplane.txt coordinates for BIB (555) were 
established? This is why I am cc'ing Gary. Does anyone remember how 
the values of X,Y_ihmp = 3.3  -73.2 were set for the BIB? 

  I think until we separate these 2 problems, we really don't know what 
is happening in a blind offset setup. Sorry to go on here, but any words 
about the BIB position (in ihmp) would be very helpful. 
-Steve