The solar filter 50 DS can be combined with almost all popular refractors.
In contrast to other H-alpha solar filters, the filter 50 DS no central obstruction (obstruction), which is a clear advantage in contrast ratio and sharpness of the optics.
The production of this type of solar filters is therefore difficult and expensive to be taken as such in the filters of other manufacturers also have here in making more on optical quality and mechanical precision.
The result is that larger filters of other manufacturers that cost the same or even more expensive, can not keep 50 DS by far with the sharpness and contrast of the solar filter.
By using a second spectral range of the etalon filter is reduced to a half value width of 0.5 Å. The prominences can then not be seen as good, but the surface details are becoming hugely contrast. To observe the prominences, one can again simply unscrew the second etalon.
The package consists of a Fabry-Perot etalon filter 50mm double stack with a surface accuracy of lambda 1/100, 20mm blocking filter in a 2'' version used to back in the telescope, and a 2'' -1.25'' reducer.
Not included is an appropriate adapter plate for mounting the filter in front of the lens. Default, these are available for most major telescope manufacturers.