Astronomik ASHA6nm - H-Alpha CCD Filter, 6 nm, 2 inch mounted
This H-alpha Filter is suitable for imaging of Hydrogen
nebulas from observation sites with light pollution and from dark sites
as well. The contrast between an object glowing at 656nm and the
background is increased enormous!
Due to the combination of the narrow bandwidth of 6nm and the high
transmission of typically 96% the filter gives you an enormous contrast
boost, as all unwanted light from other wavelengths than 656nm is
blocked form UV up to the IR. This results in an extremly dark
background.
The FWHM of 6nm is matched to give you optimal
performance with CCD and CMOS sensors with a very low dark current! The
6nm filter is the best choice if you are observing from a heavily light
polluted site or if you are imaging faint objects in starcrowded regions
of the milkyway.
Due to the new MFR coating technique you may use one single
filter on all instruments up to f/4 without a significant reduction in
performance.
Der Astronomik H-alpha filter MUST NOT BE USED for solar observation!
Products specifications
Typical Transmission at the H-alpha Line (656 nm)
|
96% |
Guaranteed Transmission at the H-alpha Line (656 nm)
|
>90% |
perfect blocking of unwanted light
|
from UV up to the IR |
parfokal with all Astronomik filters
|
Yes |
Coating technique
|
MFR |
Thickness
|
1mm |
Filter thread / size
|
2" |
Usable with all optics up to
|
up to f/3 |
Full-Width-Half Maximum (FWHM)
|
6nm |