Despite my affinity for the narrowband Bicolour Palette, I thought it would be a nice idea to complete the set of Astrodon narrowband filters with this one - the Sulphur-II 3nm filter. Astrodon also make a Nitrogen-II 3nm filter, of course, but the wavelength is so close to Hydrogen-Alpha, that I have not observed enough of a difference in images to push me to want it. Besides, now having the Sulphur-II filter as well allows me to produce images with the Hubble Palette if I like.
Getting this new filter into the QSI 660wsg-8 CCD camera gave me a chance to clean up any dust particles from the filters. All is now set and ready. I have my eighth filter slot unused but I do not suspect I will ever really use it. I cannot justify another £350 or so for the Nitrogen-II 3nm filter!
