Astronomy Filters for Sale
by Gary Honis
This is a brand new Astronomik H Alpha 12mn EOS Clip-Filter.
$190 plus free USPS shipping in the continental United States
The Astronomik H-alpha filter is a narrow band filter for CCD photography. The filter lets the H-alpha 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 availability of guiding stars for cameras with a built-in-autoguider (SBIG). If you use a very strong filter like our 6nm filter you often won’t find a usable guidestar.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.
Main use
The Astronomik H-alpha-CCD (12nm version) increases the contrast between objects, in this case between the H-alpha emission line and the skyglow background. Our Astronomik H-alpha-CCD (12nm version) completely suppresses the emission lines of artificial lighting (mercury (Hg) and sodium (Na)) and skyglow.
Other uses
When using the 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.
The Astronomik H-Alpha filters may NOT be used for solar observation.
If you plan to create color images from emission line data, our CLS-CCD filter is a great choice for the Luminance channel.
$190 plus free USPS shipping in the continental United States.
You can send me a personal check or money order payable to Gary Honis only to this address:
Gary Honis
24 EdgeTrail
Sugarloaf, PA 18249
Or you can use PayPal for payment just email me at
Gary