Viewing SASv12.0/50522
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Date: Mon, 09 Jul 2012 10:37:34 +0200
From: Georgiana Ogrean <georgiana.ogrean@hs.uni-hamburg.de>
To: xmmhelp@sciops.esa.int
Subject: Sky to detector coordinates

Hello,

Could you please tell me if there is a SAS tool that converts more 
complex regions (not just points or circles) from sky to detector 
coordinates? I am aware of the esky2det and ecoordconv tasks, but as far 
as I understand these only convert a sky position in detector 
coordinates. I am looking for something that can also convert, for 
example, the orientation/angle of an elliptical region. Does such a task 
exist?

Thank you,
Georgiana

Reply 1

From: Matthias Ehle <xmmhelp@sciops.esa.int>
To: georgiana.ogrean@hs.uni-hamburg.de
Subject: Re: Sky to detector coordinates (PR#50522)
Date: Mon Jul  9 10:31:34 2012

Dear Georgiana,

I suggest you have a look at the SAS task ecoordconv, see
http://xmm.esac.esa.int/sas/current/doc/ecoordconv/ecoordconv.html

I have the impression this tasks offers the functionality that 
you are looking for.

Regards,
   Matthias

--
   Dr Matthias Ehle 
   XMM-Newton User Support Group
   European Space Astronomy Centre

Followup 1

Date: Mon, 09 Jul 2012 20:32:48 +0200
From: Georgiana Ogrean <georgiana.ogrean@hs.uni-hamburg.de>
To: Matthias Ehle <xmmhelp@sciops.esa.int>
Subject: Re: Sky to detector coordinates (PR#50522)

Dear Matthias,

I don't think ecoordconv does what I need. For example, I attached the 
output of:

ecoordconv imageset=mos1S001-obj-im.fits srcexp='(RA,DEC) in 
ellipse(341.02801,53.232776,100,50,45)'

at the end of this email. Above, the semi-axes of the ellipse are in 
arcsec, so the detector values should be the radii in arcsec divided by 
0.05. But there are no similar values in the ecoordconv output.

Also, the output of the command above is identical to that of:

ecoordconv imageset=mos1S001-obj-im.fits srcexp='(RA,DEC) in 
ellipse(341.02801,53.232776,100,50,0)'

which is the same ellipse as above, but with a zero orientation/angle in 
equatorial coordinates.

Georgiana



ecoordconv:- Executing (routine): ecoordconv 
imageset=mos1S001-obj-im.fits srcexp='(RA,DEC) in 
ellipse(341.02801,53.232776,100,50,45)' x=0 y=0 coordtype=eqpos 
withcoords=no  -V 5
ecoordconv:- ecoordconv (especget-1.31.4)  [xmmsas_20120523_1702-12.0.0] 
started:  2012-07-09T18:17:18.000
ecoordconv:- Data mode: IMAGING
ecoordconv:- Window mode: 0 [PrimeFullWindow]
ecoordconv:-  Units set to: 0.05 0.05
ecoordconv:- det centre: 6715.38 6407.16
ecoordconv:- det centre: 6605.3 6605.3
ecoordconv:- Array datatype 6
ecoordconv:- Searching for closest pixel to source region centre
ecoordconv:- X : 229.225 452.831 1 900Y: -58.5706 165.036 1 900
ecoordconv:- Found 810000 in filtered table.
ecoordconv:- ImageRegion: constructed with (RA,DEC) in 
ellipse(341.02801,53.232776,100,50,45)
ecoordconv:-  Setting up source pos: 25946 25946 EQPOS
ecoordconv:-  Set up source image region
ecoordconv:-  Region Centre:
  Theta: Phi: 93.2943 2.2321
  X: Y: 25946 25946
  DETX: DETY: -1373.45 -1355.06
  RA: DEC: 340.796 53.1094
  RAWX: RAWY: 238 239
  CCD(s):  1 2 3 4 5 6 7 centred on CCD: 1

Reply 2

From: Matthias Ehle <xmmhelp@sciops.esa.int>
To: georgiana.ogrean@hs.uni-hamburg.de
Subject: Re: Sky to detector coordinates (PR#50522)
Date: Tue Jul 10 09:53:53 2012

Dear Georgiana,

I checked also with the SAS team: actually there is no specific SAS task that 
does the job. 

Maybe you can write a small script, which of course could use existing SAS 
conversion tasks. 

Sorry that we have no better solution for you here.

Cheers,
  Matthias