The IDAS HEUIB-II (H-alpha Enhanced UV IR Blocking) filter is designed for enhanced spectrum DSLR's and one-shot color CCD astronomical cameras.
Besides removing the IR and UV ends of the spectrum which are often out of focus in refractive optics, it isolates the common H-alpha line relative to the surrounding extreme red end of the spectrum, making it easy to bring out the faint H-alpha emission nebulosity of astronomical photos, yet retain the background color balance of broadband photos.
Available in 52mm and 48mm sizes mounted in standard camera filter rings, 37mm size mounted for the Canon MFA, and unmounted in 36mm and 49mm sizes. The filter is also available as a Nikon front filter.
Price does not include shipping and brokerage, which will be confirmed before actual payment is taken.