Heliostar 76mm H-Alpha - Skywatcher

Sky-Watcher, the world leader in astronomy equipment (telescopes/scopes/mounts), is now launching solar filters! For maximum viewing pleasure, Sky-Watcher now offers an instrument equipped with an H-Alpha filter. Complex to make (compared to white light filters), it allows us to see the Sun in a "different light" through the Hydrogen Alpha spectral line at 656.3 nm. It is then possible to see our "living" star by observing its surface bubbling (granulation)... and its impressive prominences (gigantic jets of high-temperature gas expelled into the interstellar void). The disk, then perfectly defined, becomes dotted with fine filaments at its edges... or shadows on its surface. Sunspots appear slightly differently and are generally surrounded by hotter active zones (flares).

The filtration process used, the heart of an "H-Alpha telescope" is called: Fabry-Perot standard. Its principle consists of placing 2 parallel-faced plates with a high-reflectivity coating. The incident beam is split then recombined and according to the principle of the wave nature of light, the superposition gives rise to interferences which generate shadowy or bright areas. Depending on the thickness between the 2 plates and the angle of incidence, some wavelengths will be free to pass through the Fabry-Perot and others not.

The bandwidth is adjusted using a tuner system that modifies the pressure and tilt angle of the Fabry-Perot etalon plates. Make sure the Heliostar 76α is placed outdoors for more than half an hour before each use to ensure a constant temperature inside and outside the etalon, which will improve your observations and photography.

Accessories: Sky-Watcher offers a wide range of accessories to complement the Heliostar 76mm. It comes in a hard-shell carrying case, which is very practical for travel. A sun pointer allows you to orient your instrument in seconds. A high-quality eyepiece with a 20mm focal length and 70° apparent field of view shows the entire solar globe. The 11.5mm blocking filter (angled mirror) allows you to place reasonably sized sensors such as the ZWO ASI 715MC or 585MC for your imaging sessions. The eyepiece holder is a Crayford with a 50.8mm barrel, with a 10:1 gear ratio, very useful for high-magnification visuals or astrophotography. A smartphone adapter allows you to start taking your first photos!

Specifications

• Diameter: 76mm
• Optical Design: Double Achromatic
• Focal Length: 630mm
• Focal Ratio: 8.3
• Bandwidth: Less than 0.5Å
• Blocking Filter: 11.5mm
• Sun Size: 6mm
• Focuser: 2" Crayford with 10:1 Reduction
• Length: 600mm
• Weight: 3.8kg