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OFFSETS

    OFFSETS xOffset yOffset

    Specify source offsets.

    Real      :: xOffset           ! x-offset
    Real      :: yOffset           ! y-offset

    IMPORTANT NOTE: one should be careful with the OFFSETS command, which
    is only used and only needed in a few special situations, e.g., with
    Wobbler-switching ONOFF and to set NASMYTH offsets for
    focal-plane-array receivers.  The function of OFFSETS is explained in
    the paKo user's manual, Section "A Guide to the Perplexed" and, in
    more detail, in the Section "NCS Explained", Subsection "Coordinate
    Systems, Projections, and Offsets."

    For many observations all "offsets" are specified as parameters or
    options of the command for the observing mode.

    /SYSTEM systemName

    Name of system for offsets.

    Character :: systemName          ! name of system, one of:
                                     ! PROJECTION
                                     ! TRUEHORIZON
                                     ! NASMYTH

    <<TBD:                           ! DESCRIPTIVE>>
    <<TBD:                           ! BASIS>>
    <<TBD:                           ! EQUATORIAL>>
    <<TBD:                           ! HADECL>>
    <<TBD:                           ! HORIZONTAL>>

    PROJECTION for now means only the standard simple "radio" projection
    offsets in the chosen coordinate system. This is normally the
    astronomical system of offsets in which point-by-point (TRACK, ONOFF)
    or on-the-fly (OTFMAP) maps are made.

    TRUEHORIZON means the horizontal system with a factor 1/cos(elevation)
    applied to the azimuth offset.

    NASMYTH are special offsets to point an off-center pixel of a
    focal-plane array receiver (bolometer, HERA) to the commanded
    astronomical position, e.g., to use an off-center pixel for pointing,
    focus, ONOFF.

    IMPORTANT NOTE: projection, trueHorizon

       If the observing mode (LISSAJOUS, ONOFF, OTFMAP, ...)
       is in /SYSTEM projection,
       OFFSETS ... /SYSTEM projection is ignored (not used).
       If the observing mode (LISSAJOUS, ONOFF, OTFMAP, ...)
       is in /SYSTEM trueHorizon,
       OFFSETS ... /SYSTEM trueHorizon is ignored (not used).

    IMPORTANT NOTE: OFFSETS   /SYSTEM Nasmyth


       If OFFSETS xOffset yOffset /SYSTEM Nasmyth are specified in pako,
       the values xOffset yOffset are used during the observations.
       (this inludes the case that they are explicitly set to 0.0).
       It is up to the observer to make sure that they are "correct".
       (in pakoDisplay /SYS Nasmyth will be highlighted as yellow alert.)

       If OFFSETS xOffset yOffset /SYSTEM Nasmyth are not specified
       (cleared), for the MAMBO bolometer, Nasmyth offsets are used
       automatically according to the selected bolometer channel (pixel).


Subsections

Gildas manager 2023-06-01