Baader Narrowband Enforced 3.5nm H-Alpha Filter 50x50 Square 2459456
Baader Narrowband enforced 3.5nm H-alpha Filter, 50x50 mm Square
These 3.5 nm H-alpha Enforced-Narrowband Filters open up the extremely narrow 3.5nm H-alpha world.
This enforced contrast results in even fainter stars, providing more signal of faintest nebulae detail. Manufacturing such ultra-narrow filter does require extreme coating homogeneity and very high CWL precision, which these filters are designed for (CWL= Center-wavelength).
These are available in sizes: 2" Mounted (#2459454), 50.4mm round unmounted (#2459455) and 50x50mm square unmounted (#2459456)