2" H-Alpha Filter

The Astronomica H-Alpha CCD filter, is designed for CCD imaging of gaseous nebulae. Due to the narrow bandpass of the H-Alpha line at 656 nm, the filter will provide a great increase in contrast, even under poor observing conditions, including full moon! The 15 nm bandwidth allows transmission as high as 90%,to be achieved. With faint supernova remnants and planetary nebulae, the Astronomica H-Alpha filter often makes the difference between detecting the object or not. The filter blocks all unwanted light, especially the Mercury (Hg) and Sodium (Na) emissions from streetlights and the IR region where CCDs are often most sensitive.