Solar Coronagraph

The sun in coronagraph © Günter Stein

With the BelOptik Solar Prominence Viewer or Prominence Scope (similar to coronagraph) you can observe chromospheric details like protuberances on the edge of the sun in very high contrast. The device generates an artificial solar eclipse and reduces stray light from the lens of the telescope through an iris baffle.

A conical baffle in the telescope focus completely hides the sun. The cone is mounted on a second auxiliary lens. This lens projects the main objective on an adjustable iris baffle. This iris baffle will be closed to reduce light scattering from the edge of the main lens, so far that the background is dimmed. A projection objective is arranged behind the iris aperture. With an eyepiece in secondary focus of the projection lens you can see the edge of the conical baffle. A very narrow band interference filter (FWHM <1nm = 10A) between the projection lens and the eyepiece allows the observation of solar prominences in wavelength of ionized hydrogen on the edge of the cone. The filter is mounted in an adjustable tilt cell. The prominences of the sun will be visible in high contrast against a dark background.
The BelOptik Coronagraph will equipped with either an H-alpha filter or H-beta filter. You can choose. (See also article solar prominences in H-beta light from german magazin „Sternzeit“)

coronagraph components

The optical components are multicoated and blackened edges and the tubes based on T2 mount system.
The Prominence Viewer is delivered in a padded aluminium case.

Price on request

The Prominence Viewer will be mounted directly on the focuser of the telescope with T2 thread or 2" barrel. The sun changes its apparent angular diameter in the sky during a year. Therefore I deliver at least three different cone aperture diameter. These cones can be simply screwed onto a thread in the auxiliary lens.
Tip: Use an equatorial mount with motorized tracking system because the observation and handling is easier and glare can be prevented.