Chroma has made a set of Ha, OIII and SII 3nm that are optimized for F/3 beams by moving the center wavelength slightly into the red so they will shift slightly to the blue when used in an F/3 beam, thus maximizing transmission at the nominal wavelength. For beams faster than F/3, we recommend using 5nm-wide or wider bands.
Best in Class Filters
Chroma filters are widely recognized as being some of the best in astrophotography. The versatility of Chroma manufacturing is also highlighted in these filters designed for fast telescopes, separate to the standard filters they produce as well. No matter what kind of imaging you're planning for, these American made filters are sure to satisfy any imager's needs.
Made in the U.S.A.
Designed and manufactured here in the U.S.A., you can be sure that these filters will be up to par with the extreme quality control required for astrophotography. On top of this, buyers here in the U.S.A. will not have to wait long at all to receive their filters--so long as they're in stock, that is! The immense popularity of Chroma brand filters keeps the company at peak performance to maintain supply for an always increasing demand.
OIII filters allow almost all of the light to pass through that transmits at the spectral lines of 496 and 501 nm while blocking nearly everything else