Description:
Masks
defined by SNR limits can show instabilities in which pixels can repeatedly enter the mask on one
iteration and leave it on the next. Such oscillating pixels tend to occur around the edges of source areas
in the mask, and can prevent convergence of the iterative map-making process. Setting
AST.ZERO_ACCUM to a non-zero value can prevent this by forcing source pixels to be accumulated
rather than replaced on successive iterations. Thus, if AST.ZERO_ACCUM is non-zero, any map pixel
which is flagged as a source pixel on some iteration will never be unflagged - once a source
pixel, always a souce pixel. [0]
Type:
integer SMURF Usage
MAKEMAP, CALCQU
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