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IMPORTANT notes sent to the SAs for the  INGRID 
nights after the 21st of March
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**The mechanisms are not reliable or repeatable in some cases.
  Therefore, the number of movements is restricted and observers 
  can only use ONE filter per night.

  The observer should meet the DE in the afternoon to confirm which 
  is the configuration he/she needs that night (pupil stop/filter wheel1/
  filter wheel2), or send an e-mail the previous day to Kevin and the 
  DEs of the incoming days.

  According to the schedule, the DE of the following days (from
  26 to 31 of March) are:

  srb,ejm,cwmj,ejm,pcm,cwmj

  At the end of the night the observer should leave a blank in 
  one of the filter wheels and can then take darks.
  
  e.g. SYS> fwheel2 ingrid blank1

 (It is not needed to put blanks in both filter wheels and this 
  minimize movements) 

  This restriction implies that observers can NOT take darks in 
  the afternoon (only in the morning). 

  The old cass-l and cass-s have been repalce by cass-j, cass-h
  and cass-k (to be used with j,h,k(and ks) filters respectively).
  I am going to update the new configurations in the webpage:


http://www.ing.iac.es/Astronomy/instruments/ingrid/ingrid_cookbook.html#3.

  so that observers can easily check the configuration they need.

**The detector is translated from its nominal position 
  inside INGRID by ~1.1mm (60 pixels=~14") up.
  Therefore the rotator center of the telescope is ~14" down 
  from the center of the array.
 
  Rotator center aprox at ~(480,454)

**As you may know, image quality is not good at the moment. At 
  the best focus position, the ellipticity is ~20-30%.
  We are investigating this, but it seems to be due to the 
  telescope (or the INGRID flat mirror moving?).

**Focussing the instrument/telescope.
  Taken into account the previous point, there is no need to
  focus both the telescope and instrument.
  
  I suggest to leave the instrument focus fixed at +900 microns
  and then focus the telescope in the usual way (use focusrun)
  (The best telescope focus will be ~98.65mm).

  Tell the observers to make sure at the beggining of the 
  night that the instrument focus is +900 microns.
  If that is not the case, call the DE or type 

  SYS>ifocus ingrid +900

**Plate scale is now again 0.244"/pix

**I have checked the linearity and it is the same than 
  it was before (non-linearity ~+/-2% from 0-12000 ADU).
  
**readout noise is ~4-6 ADU  (==> 16-30 e-)
  
 Due to the fact that all this situation will change soon (I hope!!!),
 I am not changing the webpages to include all these notes
 (just the filter wheel combinations for each filter).
 
 Please, contact me or phone me at home or use my mobile phone (607439347)
 if you need something during your runs.

 Cheers,
	Almu