==== Science IFU template METIS_ifu_obs_FixedSkyOffset ====

=== Procedure for METIS_ifu_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|
  * This template moves the telescope or the chopper alternatively between OBJECT and SKY positions, and performs a specially designed sequence of offsets in the across-slice direction and rotation in order to achieve equal spatial sampling in both directions.
    * Take three OBJECT-SKY pairs of images, the first one at the initial position, and the other two after offsetting each time by ~1/3 of a slice width in the across-slice direction.
    * Rotate the field by 90 degrees and repeat the steps from previous point.
  * The above-described sequence is repeated ''NCycles'' times, and at each repetition, the OBJECT and SKY positions can slightly change.
  * The OBJECT positions are randomly distributed around the initial telescope position and within a box defined by the parameter ''Jitter Box Width'' (in arcsec).
  * The SKY positions are randomly distributed around a position set at a constant distance from the initial telescope pointing. This distance is defined by the parameters ''Sky offset in RA'' and ''Sky offset in DEC''. The dither around this position is calculated to be within a ''Jitter Box Width''.
  * Offsets to sky and dithering are performed using the CFO-PP2 chopper or telescope offsets (TBD).
  * Offset the chosen actuator (telescope or chopper).
  * There are gaps in the instantaneous wavelength coverage of the LMS, which can be accounted for by tilting slightly the main dispersion grating. The user can select the angle of the dispersion grating from a list of pre-defined named positions, or can explicitly specify the desired angle (TBD).
  * The science sequence is repeated at each setting of the main dispersion grating angle. 
  * At each offset position start science exposures with both the LMS and the IMG-LM detector. The DIT/NDIT of both detectors will be computed by the template based on the requested total exposure time.
  * 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 or chopper (depending on which actuator is used for offsetting) back to the initial position.
  * Collect headers
  * Merge into one or more data cubes
  * Send cube to ESO Archive
  * Send cube to Pipeline machine or ICS storage (tbd)
  * Go back to //Setup IFU// until target observations are finished (single OB). For example, to observe at a different central wavelength.

At the end of the OB:
  * Stop chopper
  * Stop CFO pupil stabilization
  * Stop AO
    * open loop
    * stop field stabilization
    * stop registration
    * stop modulation
  * Stop derotator
  * Handover to telescope
    * CCS takes control of M4 and M5
    * Telescope gets ready for next preset
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===Parameters for METIS_ifu_obs_FixedSkyOffset===

^Parameter             ^Hidden     ^Range (default)            ^Label^  
|DPR CATG              |yes        |SCIENCE TEST (SCIENCE)     |Data product category|
|DPR TECH              |yes        |IFU (IFU)                  |Data product technique|
|DPR TYPE              |yes        |OBJECT SKY (OBJECT)        |Data product type|                      
|DET1 DIT               |yes         |0..TBD (NODEFAULT)         |IMG-LM Detector integration time (DIT)|
|DET1 NCORRS NAME       |no         |TBD                         |IMG-LM Readout mode|
|DET3 DIT               |yes         |0..TBD (NODEFAULT)         |LMS Detector integration time (DIT)|
|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 JITTER WIDTH      |no         |0..5 (NODEFAULT)           |Jitter Box Width (arcsec)|
|SEQ NCYCLES         |no         |0..100 (NODEFAULT)         |Number of observing cycles|
|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 DET1 NDIT OBJECT       |yes         |1..1000 (NODEFAULT)       |NDIT on OBJECT positions IMG-LM|
|SEQ DET1 NDIT SKY          |yes         |1..1000 (NODEFAULT)       |NDIT on SKY positions IMG-LM|
|SEQ DET3 NDIT OBJECT       |yes         |1..1000 (NODEFAULT)       |NDIT on OBJECT positions LMS|
|SEQ DET3 NDIT SKY          |yes         |1..1000 (NODEFAULT)       |NDIT on SKY positions LMS|
|SEQ NEXPO             |no         |1..1000 (NODEFAULT)        |Number of exposures per offset|
|SEQ OFFSET COORDS     |no         |SKY DETECTOR (DETECTOR)    |Offset coordinate type selection|
|SEQ SKYOFFSET ALPHA   |no         |0..TBD (10)                |RA offset to sky|
|SEQ SKYOFFSET DELTA   |no         |0..TBD (10)                |DEC offset to sky|
|SEQ POISSON           |yes        |1..100 (10)                |Random throw generator
|SEQ RETURN            |no         |T F (T)                    |Return to origin?|
|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|