==== Science spectroscopy template METIS_spec_lm_obs_AutoNodOnSlit ====

=== Procedure for METIS_spec_lm_obs_AutoNodOnSlit ===
 
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Setup spectrograph|
  * Move to selected filter (''IMG-LM PP1 FILT'') 
  * Move to selected grism (''IMG-LM PP1 MASK/GRISM'')
  * Remove the neutral density filter (''IMG-LM PP1 ND'' to open)
  * Set detector parameters (DIT, NDIT, readout mode, cube mode T/F)
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Start science exposures|
  * This template performs offsets between two positions (A and B) along the slit. A cycle is a pair of AB or BA observations. Cycles are repeated on ABBA sequences. Offsets are performed both using telescope offsets, and CFO-PP2 chopper. 
  * Set up offset parameters (chopper frequency if chopping is to be used, ''NodThrow''). Position angle is fixed to match the slit orientation.
  * First science exposure is taken at the position A, by offseting to the position +''NodThrow''/2 along the slit. The second exposure (B) is taken at (-''NodThrow''/2) from the initial position along the slit.
  * Allow small random dithers along the slit around the positions A and B (using CFO-PP2 chopper or telescope offsets), defined by the parameter ''JitterWidth''. The random offsets are generated inside the interval (-''JitterWidth''/2,+''JitterWidth''/2) around the A (B) positions at +''NodThrow''/2 (-NodThrow/2). ''JitterWidth'' should be smaller than ''NodThrow''.
  * Set up parameter ''N_ABCycles'' defining the number of AB or BA cycles.
  * Set up parameter ''Nexpo'' defining the number of images taken at a single offset position.
  * At each offset position start science exposures with DIT/NDIT/readout mode. 
  * 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_spec_lm_obs_AutoNodOnSlit===


^Parameter             ^Hidden     ^Range (default)            ^Label^  
|DPR CATG              |yes        |SCIENCE TEST (SCIENCE) |Data product category|
|DPR TECH              |yes        |LSS (LSS)                 |Data product technique|
|DPR TYPE              |yes        |OBJECT (OBJECT)|Data product type|                      
|DET1 DIT               |yes         |0..TBD (NODEFAULT)         |IMG-LM Detector integration time (DIT)|
|DET1 NDIT              |yes         |1..TBD (NODEFAULT)         |IMG-LM Number of Integrations (NDIT)|
|DET1 NCORRS NAME       |no         |TBD                         |IMG-LM Readout mode|
|DET1 CUBE MODE        |yes         |T F (T)                    |Toggle cube mode| 
|INS OPTI3 NAME        |no         |A_19 B_29 C_38 D_57 E_114 (NODEFAULT)   |Slit|
|INS OPTI9 NAME      |no         |GRISM-L GRISM-M (NODEFAULT)   |IMG-LM mask/grism wheel|
|INS OPTI10 NAME         |no         |full_L full_M (NODEFAULT)     |IMG-LM Filter name|
|INS OPTI11 NAME         |no         |OPEN ND1 ND2 ND3 ND4 ND5 (NODEFAULT)  |IMG-LM Neutral density filter|
|SEQ TIME              |no         |0..TBD (NODEFAULT)         |Total integration time (sec)|
|SEQ JITTER WIDTH      |no         |0..5 (NODEFAULT)           |Jitter Box Width (arcsec)|
|SEQ NABCYCLES         |no         |0..100 (NODEFAULT)         |Number of AB or BA cycles|
|SEQ NEXPO             |no         |0..1000 (NODEFAULT)        |Number of exposures per offset|
|SEQ POISSON           |yes        |1..100 (10)                |Random throw generator
|SEQ RETURN            |no         |T F (T)                    |Return to origin?|
|SEQ CFO CHOP POSANG       |yes        |0..360 (0)             |Chopper position angle|
|SEQ CFO CHOP FREQ         |yes        |0..5 (0)               |Chopping frequency|
|SEQ NODTHROW        |yes        |TBD                        |Nod throw|

__Notes:__

  * NODTHROW parameter defines the 1D offset along the slit, with respect to the central position (as described above). 
