I just saw that Astro-Hutech announced a new dual narrow-band filter for one-shot color cameras. Based on the short write up it is looks like it is going to be more narrow that the IDAS NB1 at 10nm. The write also notes that these filters will maintain the original transmission rate even if there is a spectrum shift. Looks really promising. Price is very reasonable as well, especially when compared to the Triad filters.