The images calculated by the DA are stored as NDF extensions in the raw data files under .MORE.SCU2RED.In where n is an integer (non-zero-padded). Each image is an average of the data in typically 1 second. Note the final image is created from whatever samples remain if the duration of the file is not an integer number of seconds. Each image has its own FITS header associated with it which contains values which vary between images.
SMURF -- the Sub-Millimetre User Reduction Facility