The RM-20B mosaic differs from the types of systems that have been investigated in the past in that it only responds to image intensity modulation in its image motion-compensated (stationary) field of view. These intensity variations could be the result of either target motion or absolute radiance level shifts. If the background is relatively constant within the frequency band of interest, the number of false signals that are generated by the detector will be greatly reduced and the signal-to-noise ratio will be improved, resulting in a higher probability of target detection and lower data rates. If, however, the background has scintillation within the sensor bandpass, noise signals will be produced. No flights to date have made any measurements of background short-time (less than a second) variations. This paper discusses one attempt at obtaining mosaic data.