Astronomik H-Beta 12 nm Visual Filter - 2"

Astronomik H-Beta Visual Filter - 2"

• 2" threaded cell mounted round filter for visual purposes

• Allows light from H-Beta emissions to pass while obstructing nearly the entire remainder of the spectrum as well as IR

• Approximate FWHM bandwidth of 12 nm

• This 2" H-Beta Filter is parfocal with all other filters from Astronomik

• German-designed for superior quality optics!

Astronomik's 2" H-Beta Filter is a superb narrowband emission line filter for CCD imaging applications as well as visual observation. It permits H-Beta emission line nebulae to be transmitted while simultaneously blocking nearly the entire rest of the spectrum where the CCD is sensitive. This filter's 12 nm FWHM (full width at half maximum) enables extremely fast optics when using common CCD cameras. The Astronomik H-Beta 12 nm Visual Filter features a transmission of up to 98%. An additional benefit of 12 nm filters is the improved guide star availability for cameras with a built-in autoguider.

Full blockage of artificial emission lines from sources such as sodium and mercury-vapor is provided by the Astronomik H-Beta 12 nm Filter. It highlights the contrast between H-Beta emission line objects and the background sky. The optimal aperture ratio is 1:4.5 to 1:6, and the application range extends from 1:3.5 to 1:15. Transmission losses and chromatic distortions, while a more frequent nuisance with other filters, only occur with Astronomik filters when much brighter aperture ratios of 1:2 and more come into play.

As with all Astronomik filters, the 2" H-Beta Filter is parfocal with all other filters produced by Astronomik. It offers complete suppression of all undesired visible light and IR spectral wavelengths. Provides total resistance against the impacts of scratching, aging, and high humidity. All Astronomik filters arrive in a durable plastic storage container of superior quality.