jasonjeremiah

Late to the party but hopefully this info will benefit someone. James Thompson done a lot of extensive testing with virtually every filter used in astrophotography, including the IDAS filters. I've attached the PDF copy of his study on all of the IDAS filters being made at the time, including the NB2, NB3, and NBZ. His findings show the width of the Sii bandpass to be 18.5 and Oiii bandpass 21. Their narrowest Dual Band the NBZ has a bit narrower bandwidth at 12 for Oiii and 10 for Ha. I use the Optolong L-Enhance in conjunction with the IDAS NB3 and have produced some very fine SHO images with the combo. I disdained the L-Extreme and sold it after 2 imaging sessions. I couldn't stand the massive halos around all bright stars. I don't mind the extra bandpass width of the L Enhance and prefer it when using my really fast scopes, such as my Sharpstar or Hyperstar. I do find the Oiii data from the NB3 to be weaker, but a big part of that is the narrower bandwidth in the Oiii. I don't toss the Oiii data from the NB3, but will linear fit it to the L Enhance Oiii data and then combine them in PixelMath for my final Oiii channel. TestReport-IDASFilterComparison_Nov2021.pdf