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MAP_ROBUST

      MAP_ROBUST     Real

    Robust weighting factor. A number between 0 and +infty.

    Robust weighting gives the natural weight  to  UV  cells  whose  natural
    weight  is  lower  than  a  given threshold. In contrast, if the natural
    weight of the UV cell is larger than this threshold, the weight  is  set
    to  this  (uniform) threshold. The UV cell size is defined by MAP_UVCELL
    and the threshold value is in MAP_ROBUST.

    0 means natural weighting, which is optimal for point sources.  The  Ro-
    bust  weighting factor controls the resolution: better resolution is ob-
    tained for small values (at the expense of noise), resolution  approach-
    ing  the natural weighting scheme for large values.  Larger UV cell size
    give higher angular resolution (but again more noise).

    MAP_ROBUST around .5 to 1 is a good compromise  between  noise  increase
    and angular resolution.


Gildas manager 2023-06-01