Sky-Watcher Heliostar H-alpha 100 mm OTA

Heliostar 100 Hα — dedicated hydrogen-alpha solar telescope

The Heliostar 100 is a dedicated 100 mm hydrogen-alpha solar telescope with a 760 mm focal length and a bandpass below 0.5 Å. It is designed to reveal prominences and solar hydrogen-alpha detail using its integrated filtering system.

Optical system

The 100 mm model uses a pressure-tuned Solis etalon and a 20 mm blocking filter in its dedicated solar diagonal. Sky-Watcher gives a 7.6 mm solar image and 20 mm backfocus.

Mounting and focusing

The OTA weighs 6 kg and measures 760 mm according to the product specification. Its solar guider provides aiming assistance; tune and focus using the manufacturer’s operating procedure.

Essential solar configuration

Observe only with the complete, undamaged original solar-filter system and its dedicated solar diagonal fitted as instructed. Replacing the solar diagonal with an ordinary star diagonal removes essential filtering. Read the manufacturer’s solar operating instructions before use.

Sky-Watcher manufacturer documentation

Compatibility notes

Dedicated H-alpha configuration only. The 20 mm blocking filter is part of the necessary original solar diagonal, not a normal diagonal or white-light filter.

Additional specifications