I was the developer of the narrowest calcium filter system ever owned by an amateur in 2017, and this timelapse I recorded with the system got me published. Now dozens of people use the very filter system I released to the public.
Explore scientific FirstLight 127mm x 1200mm telescope
1,5 angstrom calcium filter double stacked operating at 393.377nm (not lunt, not coronado)
meade 2x telenegative shorty barlow
Basler aca1920-155um monochrome camera
25 video acquisition frames stacked per single frame , stacked with autostakkert!3, image alignment with registax v5 and sharped with gimp unsharp mask filter.