I've heard of double stacking a Coronado but I just saw an image on page 77 of the new S&T that the caption says was taken "with stacked DayStar and Coronado" filters. Any ideas how DayStar and Coronado filters can be stacked? If we can figure it out we could try it at SPOC. patrick p.s. 30 minutes to the start of umbral eclipse and the skies remain clear. Fingers crossed...