6) Now I like to tweak the settings for optimization. The Lower quality setting determines the cutoff for where Registax will stop optimizing frames. This feature is mainly to save time since you don't want to optimize frames you plan to throw out anyway.
7) For this image I'm going to initially decide to eliminate the lower 60% of the images so I look at the value of the red quality curve for the point where 40% of the images fall under the curve. This looks like about 73% so that's what I will set the Lower Quality setting to.
8) Hit the Optimize button and the alignment will be refined for all images up to the point where you see the blue line become dashed.