If ast.zero_snr_fwhm is non-zero, the map-maker produces two maps: the first is created normally using the mask specified by parameter "ast.zero_snr" . The final SNR-based mask associated with this map is then smoothed using a Gaussian with FWHM equal to the ast.zero_snr_fwhm value (in arcsec). The whole iterative map-making process is then run again from the start, using this smoothed mask on every iteration, to create the final map. Consequently, setting ast.zero_snr_fwhm causes the time taken to create the final map to nearly double. [0.0]

MAKEMAP, CALCQU