Howard, I forgot to mention the all important "Quality estimator - Lowest Quality" [percent] filter on the "Align" tab. This controls the number of rejected vs. accepted images-for-stacking based on an abstract scalar. So, for an avi movie file of a planet or a larger number of fits or jpg images saved from a short exposure time on a bright planet, you might want to try 95% first. If the resulting filtered and stacked image looks bad, ramp the "lowest quality" value back to 90%. Repeat going down to atleast 75% until you get the best image with the highest quality filter percentage. There is no reset button on the Align tab, but you can run it multiple times reseting the "lowest quality" percentage until you get the best result. - Kurt