INGRID notes

INGRID images orientation
Plate scale change versus instrument-telescope focus
Relation telescope focus-INGRID focus
Commands to move the pupil imager
Tests reports
Detector monitoring

Other notes:

INGRID images orientation

When INGRID is in the lab, the CCC is up.
When INGRID is in Nasmyth (when used with NAOMI), the CCC is up.
When INGRID is at Cass, the CCC is down.
When INGRID is with the CCC up, the orientation of the image as recorded by UltraDas, is the same than the orientation of the object.
INGRID optics invert the image, and the UltraDas software does it also (flip in y), to compensate for that.
The pupil imager inverts the image.

Plate scale change versus telescope-instrument focus

The plate scale of the INGRID array changes when changing the position of the secundary mirror and the position of the detector to get images in focus onto the detector. Different configurations of telescope and instrument focus will then give different values of the plate scale.

In order to quantify this changes, in focus images with different configurations of telescope and instrument focus were taken on the 25th of April of 2002 for the open cluster M67. The plate scale was measured using an image of the cluster with tel. focus 98.3mm and INGRID focus -1200 microns. Then, the position in pixels of 10 stars in all images was measured, and computed the relative distances in pixels between all them (45 distances in total). The comparison between the distance in pixels of each pair of stars in all the images taken with different focus values yielded the following info:

  focus run               INGRID focus     WHT         plate scale 
or image name                             focus  
--------------------------------------------------------------------------
  ifocus3/                 ING=+1250    tel=99.20   x/1.03746 = 0.236"/pix
  ifocus1/                 ING=600      tel=99.00   x/1.02721 = 0.238"/pix
  focus1/                  ING=0.0      tel=98.70   x/1.01889 = 0.240"/pix
  focus3/                  ING=-530     tel=98.60   x/1.01069 = 0.242"/pix
  ifocus4/                 ING=-550     tel=98.50   x/1.01107 = 0.242"/pix
  ifocus5/                 ING=-1100    tel=98.30   x/1.00301 = 0.244"/pix
m67tel98.3ing-1200.fits    ING=-1200    tel=98.30           x = 0.245"/pix

(data in /scratch/fs4b/almu/ingrid/25april)

Therefore, the greater the value of the telescope focus, the greater the plate scale.
The maximum change of the plate scale when the telescope focus changes from 98.3 to 99.2 mm is 0.009"/pix (i.e. ~4%).

Relation telescope focus-INGRID focus

For the data of the table above we can plot the relation between the telescope focus and the INGRID focus to focussed images onto the detector:

The slope of the fit to the data is 2609 microns/mm, i.e. it is necessary to increase the instrument focus by +260 microns when the telescope focus increases by 0.1mm.

Commands to move the pupil imager

pupil_imager ingrid in

pupil_imager ingrid out

pupil_imager ingrid block

pupil_imager ingrid datum

Tests reports

Increase in the number of hot pixels (13-November-2003)
k-emissivity investigation plan for next standdown (October-2003)
Status of filters (INGRID+others) (27-August-2003)
NAOMI+INGRID pupil stop sizes (21-August-2003)
Detector quality checks with PCI (27-June-2003)
Hartmann tests with pinhole mask (19-May-2003)
Pupil stop wheel repeatability tests (NAOMI stops) (4-April-2003) (plot1 (naomi-obs), plot2 (naomi-clr))
Pupil stop wheel repeatability test (backward movements) (4-April-2003)
Pupil stop wheel repeatability test (foreward movements) (27-March-2003)
Pupil stop wheel repeatability tests (CASS stops) (8-March-2003) (plot1 (cass-j), plot2 (cass-k))
Pupil stop wheel repeatability tests (6-March-2003) (plot)
k-emissivity tests (6-March-2003)
Quality checks with SDSU-1 and SDSU-2 (spare controller) (11-December-2002)
Status of INGRID filters (22-November-2002)
Hartmann tests with pinhole mask (repeatibility of focus drive) (22-October-2002)
Hartmann tests with pinhole mask (21-October-2002)
Alignment (26-April-2002)
Tests on-sky (25-April-2002)
Conclusion from tests (dome closed) (3-March-2002)
Alignment (3-March-2002)
Image quality (3-March-2002)
Notes for SAs supporting after the 21st of March (22-March-2002)
Tests on-sky (21,22-March-2002)
Autoguider tests (26-Jan-2002)

Detector monitoring

Hot pixels - Cookbook for monitoring the number and distribution of hot pixels in the INGRID array.
Linearity - Cookbook for measuring INGRID array linearity.

Last Updated: 2 January 2003
Almudena Zurita, azurita@ing.iac.es