Provides alternative method for SNR masking
"
ast.zero_snr"
to be created using
an algorithm like that used by the KAPPA command "
FFCLEAN"
(see SUN/95), instead of using a simple
thresholding of the SNR map. The parameter "
ast.zero_snr"
gives the clipping level of the ffclean algorithm,
and the parameter "
ast.zero_snr_hipass"
gives the box size. Using an ffclean algorithm prevents
the source regions within the mask being larger than the box size, and may thus produce faster
convergence and avoid blobs developing. [0]