I am always impressed with astro images posted in the journal and magazines.I am ordering a StralightXpress filter wheel to fit the H9 camera. While I was at Cambridge attending the Webb Society meeting I looked at Baader filters. The sets come in two types of narrowband filters. One set of 4 have a wider bandwidth and a cheeper than the lower band width. I gather that the low bipass filters take about 4 times the total exposure. Astro imagers any opinions?