Please note: This text was taken directly from the manufacturer.
The S-II filter passes light at the 672.4nm wavelength (the Sulfur-II line in the deep red end of the visual spectrum) with very high 90 percent transmission and a bandpass of 7nm. It complements the Orion H-alpha and Oxygen-III extra-narrowband filters, which together allow advanced tricolor imaging of emission nebulas with the StarShoot Deep Space Monochrome CCD Imaging Camera or other monochrome CCD cameras. So if you're ready to go beyond RGB imaging and capture your favorite nebulas in a revealing new light - no matter how light-polluted your skies -- add our S-II (and O-III and H-alpha) Extra-Narrowband filter to your imaging arsenal! Includes protective plastic case.
