Astronomik H-Beta CCD Filter

The Astronomik H-beta filter is a narrow band emission-line filter for CCD photography. The filter lets the H-beta light of emission nebulae pass and blocks nearly the whole remainder of the spectrum where the CCD is sensitive.

The full width at half-maximum (FWHM) of 12nm is optimized for the use with common CCD cameras and allows the use of very fast optics. It should be noted that the filter has a transmission of up to 99%.

Another advantage of the 12nm filters is the better availability of guiding stars for cameras with a built-in-autoguider (SBIG). If you use a very strong filter like our H-alpha 6nm filter you often won’t find a usable guidestar.

Together with the other three Astronomik emission-line filters you can do great color images even from very light polluted places!

The filter has a built-in IR-blocker up to 1150nm. You don’t need an additional IR-blocker with this filter.

Main use
The Astronomik H-beta-CCD increases the contrast between objects, in this case between the H-beta emission line and the skyglow background. Our Astronomik H-beta-CCD completely suppresses the emission lines of artificial lighting (mercury (Hg) and sodium (Na)) and skyglow. The optimal aperture ratio for this filter is 1:3.5 to 1:6. The range of application extends from 1:2.8 to 1:15. Transmission losses and chromatic distortions, which arise with other filters, only occur with Astronomik filters when extremely bright aperture ratios of 1:2 and more come into play.

Other uses
When using the Astronomik H-beta CCD filter together with the H-alpha CCD, OIII-CCD and the SII-CCD filters you can obtain three-color images of emission line objects (gas nebulae) from locations with very strong light pollution. To do so, you would take an image in three different wavelengths, select each one as a color-channel in Photoshop and paste them together as a color image.
When using the Astronomik H-beta filter together with the H-alpha-CCD you can create charts of the ionization energy in nebulas by creating an image from the ratio of H-alpha vs. H-beta.
If you plan to create color images from emission line data, our CLS-CCD filter is a great choice for the Luminance channel
The H-beta-CCD is also great for visual observation. If you plan to get filters for visual observation and for astrophotography get the CCD filter: You may use this filter visual as well as in front of you camera. The built-in IR-blocker doesn’t disturb visual observation but you need an additional IR-blocker if you want to use the visual filer with your camera.