H-alpha filter passes light at 656nm wavelength. Best choice of narrowband H-alpha astrophotography filter for high-contrast imaging and revealing rich details of the nebula even in areas with strong light pollution,
Astrophotography: Black and white cameras (monochromatic cameras) are best used for this filter. Ideally, combine shots with SII, OIII and H-alpha filters. This will result in an image that shows the delicate nebula structures in high contrast and clearly.
Line filters with a 12 nanometre half-width are useful if you are using a DSLR or a CCD camera with a higher dark current. The 12 nm filters are also the first choice if your camera has an integrated guiding chip, because when using 12 nm filters, you typically have twice as many stars in the image.
