Astronomik H-beta-CCD 12nm 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.
We have re-desgined all of our photographic filters. Since the end of 2008 we are shipping our new "Halo-Free" filters. read more...
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.
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.
In contrast to purely visual filters, photographic CCD filters have built-in IR-blocking, which prevents the optical problems caused by infrared radiation.
Please note: In principle, all camera lenses can be used with the Clip-Filter - i.e. Canon EF lenses or camera lenses from other third party manufacturers such as Sigma, Tamron, Tokina, Walimex etc. However, the use of clip-filters with Canon EF-S lenses is NOT possible!