MAP_CONTINUUM SCM

        [ADVANCED\]MAP_CONTINUUM  [DIRTY|CLEAN|Other]  /METHOD  SCM   [Threshold
    [MaxIter]]

      Compute  the  continuum  based on the per-pixel spectrum. Each spectrum is
    sigma-clipped until convergence of the noise. The method is similar  to  the
    GAUSS  method,  but more robust at the expense of lower speed because of the
    iterative median  clipping. Threshold is the number of sigma used for  clip-
    ping.  MaxIter  is  the maximum number of clipping operations performed (de-
    fault 6).

      The method does not deliver a spatially independent noise, but adapts  the
    bandwidth to the line free zones for each pixel. It may fail for pixels that
    are close to line confusion, though less than the GAUSS method.