Astrodon - Filters

Narrowband (NB) filters  enhance contrast of emission objects by accepting
only a narrow range of wavelengths around the emission lines of hydrogen
(H-a, 656 nm), oxygen (OIII, 501 nm), sulfur (SII, 672nm) and others.

The NIR region remains largely unexplored by amateur imagers. Perhaps this
is due to the impression that the Si CCD camera is not sufficiently
sensitive in the NIR.  Perhaps it is not clear what can be imaged in the
NIR.  Narrowband imaging has only recently become popular, allowing imagers
to take images from backyard equipment like the Hubble Space Telescope's
"Pillars of Creation" (Messier 16).  NIR imaging may follow this recent
narrowband evolution and become another tool in the imager's toolkit.  This
image is of Maffei 2, a galaxy in the plane of the Milky Way that is
obscurred by dust and hence, very faint.  This image was made entirely in
the NIR with no visible light!

Astrodon Tru-Balance RGB filters have revolutionized CCD imaging. Their
popularity is due to ease-of-use, high optical throughput and great
resulting color for galaxies, star clusters and nebulae.  There are two
varieties of Tru-Balance filters - E-Series and I-Series.

Astrodon Tru-Balance RGB filters have revolutionized CCD imaging. Their
popularity is due to ease-of-use, high optical throughput and great
resulting color for galaxies, star clusters and nebulae.  There are two
varieties of Tru-Balance filters - E-Series and I-Series.