Astronomik HSO 6 nm Filter Set 36 mm

Astronomik HSO 6 nm Filter Set 36 mm

If you have to observe from light polluted sites (like most of us ...), imaging with narrowband emission line filters is the best way to take great images, as all kind of light pollution can be blocked very effective!

Normaly an H-alpha filter is the most important filter. With a narrowband H-alpha filter you will be able to take deep and contrasty images even wih very heavy light pollution or with the full moon high up in the sky! If you look at other astrophotos, an H-alpha is the best choice for all nebulas glowing red.

An [O III] filter expands your imaging possibilities, as you are able to image all greenish/blueish structures. Planetary nebulas and star forming regions are great targets!

The [S II] filter completes your HSO set of filters. With these three filters you are able to process your images like the ones from the Hubble space telescope!

How it works
Each of the filters blocks all artifical light-pollution and natural airglow. Especially light from high and low pressure sodium and mercury lights and all lines of natural airglow are 100% blocked. The filter increases the contrast between objects glowing in the respective emission line and the sky background.

Practical design
The innovative MFR coating technology makes it possible to use the filters on all devices up to a focal ratio of f/4, and the design of the filters allows any orientation - optically there are no front and rear sides with different properties.

Alternative:
The 6 nm narrowband line filters are interesting if objects in very star-rich areas of the sky are to be photographed with short focal lengths, if you have a camera with very low dark current or if you are observing from a location with extreme light pollution. The number of stars in the image is typically halved.

Safety informations: PDF Download