==== Science IFU coronagraphy template METIS_ifu_vc_obs_FixedSkyOffset ====

=== Procedure for METIS_ifu_vc_obs_FixedSkyOffset ===
 
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Setup IFU|
  * User can choose the central wavelength (INS WLEN CEN) from a pre-defined list. The system then sets the order, and the grating tilt of the Echelle necessary to provide the required setting.
    * ''LMS PP4'' Select pre-dispersed range (order)
    * ''LMS PP5'' Select main dispersed range 
  * Set detector parameters (DIT, NDIT, readout mode, cube mode T/F)
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Start science exposures|
  * The observations are performed in pupil tracking, with the star always at the center of the vortex mask. The number of exposures taken at this position is set by the keyword ''N_OBJECT''
  * Start science exposures with DIT/NDIT. 
  * Every ~10 minutes a sky and an off-axis PSF measurement are taken (needed for the QACITS, which runs on the IMG-LM data):
    * The chopper is used to move the star outside of the detector field-of-view (throw ~5 arcsec), and record empty sky measurements (N_SKY exposures are taken with the same DIT/NDIT combination as the science measurements).
    * Insert the ND filter (if necessary for the off-axis PSF measurement) and take N_SKY sky measurements with the same DIT/NDIT combination as for the off-axis PSF measurement. 
    * The chopper is used to move the star back into the VPM field-of-view (~3 arcsec diameter), at a separation of more than 20λ/D from the VPM centre. An unsaturated exposure is obtained, using an ND filter if needed. The user can specify the offset value for the off-axis PSF measurement, or stick to the default value (to be optimized during commissioning).
    * Put the star back onto the VPM center (within about ~1λ/D) using the chopper. Remove the ND filter.
    * Close the QACITS loop.
  * Read-out and save individual exposures, or co-added frames, depending on the ''cube mode'' T/F keyword.


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End science exposures|
  * Return telescope and chopper back to the initial position. 
  * Collect headers
  * Merge into one or more data cubes
  * Go back to Setup Imager until target observations are finished (single OB). For example, to observe in a different filter.
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===Parameters for METIS_ifu_vc_obs_FixedSkyOffset===


^Parameter             ^Hidden     ^Range (default)            ^Label^  
|DPR CATG              |yes        |SCIENCE TEST (SCIENCE)     |Data product category|
|DPR TECH              |yes        |IFU,RAVC IFU,CVC (NODEFAULT)        |Data product technique|
|DPR TYPE              |yes        |OBJECT SKY (OBJECT)|Data product type|                      
|DET1 NCORRS NAME       |no         |TBD                         |IMG-LM Readout mode|
|DET3 NCORRS NAME       |no         |TBD                         |LMS Readout mode|
|DET1 CUBE MODE        |yes         |T F (T)                    |Toggle cube mode| 
|DET3 CUBE MODE        |yes         |T F (T)                    |Toggle cube mode| 
|SEQ TIME OBJECT       |no         |0..TBD (NODEFAULT)         |Total integration time on OBJECT position (sec)|
|SEQ TIME SKY          |no         |0..TBD (NODEFAULT)         |Total integration time on SKY position (sec)|
|SEQ TIME PSF       |no         |0..TBD (NODEFAULT)         |Total integration time on off-axis PSF position (sec)|
|SEQ TIME SKY_PSF          |no         |0..TBD (NODEFAULT)         |Total integration time on SKY_PSF position (sec)|
|SEQ DET1 DIT OBJECT    |yes         |0..TBD (NODEFAULT)        |DIT on OBJECT positions IMG-LM|
|SEQ DET1 NDIT OBJECT   |yes         |1..1000 (NODEFAULT)       |NDIT on OBJECT positions IMG-LM|
|SEQ DET1 DIT SKY       |yes         |0..TBD (NODEFAULT)        |DIT on SKY positions IMG-LM|
|SEQ DET1 NDIT SKY      |yes         |1..1000 (NODEFAULT)       |NDIT on SKY positions IMG-LM|
|SEQ DET1 DIT PSF       |yes         |0..TBD (NODEFAULT)        |DIT on off-axis PSF positions IMG-LM|
|SEQ DET1 NDIT PSF      |yes         |1..1000 (NODEFAULT)       |NDIT on off-axis PSF positions IMG-LM|
|SEQ DET1 DIT SKY_PSF   |yes         |0..TBD (NODEFAULT)        |DIT on SKY positions IMG-LM|
|SEQ DET1 NDIT SKY_PSF  |yes         |1..1000 (NODEFAULT)       |NDIT on SKY positions IMG-LM|
|SEQ DET3 DIT OBJECT    |yes         |0..TBD (NODEFAULT)        |DIT on OBJECT positions LMS|
|SEQ DET3 NDIT OBJECT   |yes         |1..1000 (NODEFAULT)       |NDIT on OBJECT positions LMS|
|SEQ DET3 DIT SKY       |yes         |0..TBD (NODEFAULT)        |DIT on SKY positions LMS|
|SEQ DET3 NDIT SKY      |yes         |1..1000 (NODEFAULT)       |NDIT on SKY positions LMS|
|SEQ NEXPO             |no         |0..1000 (NODEFAULT)        |Number of exposures per offset|
|SEQ OBSTYPE LIST      |no         |O S (NODEFAULT)            |Observation type list, O/S|
|SEQ OFFSET COORDS     |no         |SKY DETECTOR (SKY)    |Offset coordinate type selection|
|SEQ SKYOFFSET AZ      |no         |0..TBD (10)                |Azimuth offset to sky|
|SEQ SKYOFFSET ALT     |no         |0..TBD (10)                |Altitude offset to sky|
|SEQ PSFOFFSET AZ      |no         |0..TBD (TBD)               |Azimuth offset to PSF reference position|
|SEQ PSFOFFSET ALT     |no         |0..TBD (TBD)               |Altitude offset to PSF reference position|
|SEQ RETURN            |no         |T F (T)                    |Return to origin?|
|SEQ CFO CHOP POSANG       |yes        |0..360 (NODEFAULT)         |Chopper position angle|
|SEQ CFO CHOP THROW        |yes        |0..5 (NODEFAULT)           |Chop throw|
|SEQ CFO CHOP FREQ         |yes        |TBD                        |Chopping frequency|
|INS WLEN CEN         |no         |2700 - 5300 nm (NODEFAULT)           |Central wavelength|
|INS OPTI10 NAME         |no         |L' H2Oice shortL IB4.05 PAH3.3 PAH3.3ref Br-alpha Br-alpharef M' CO(1-0)/ice COref HCIL-short HCIL-long (L')                |IMG-LM Filter name|
|INS OPTI11 NAME         |no         |OPEN ND1 ND2 ND3 ND4 ND5 (NODEFAULT)                  |IMG-LM Neutral density filter|