Sky-Watcher HELIOSTAR 76 H-alpha Solar Telescope

Designed specifically for H-alpha solar observation, the Sky-Watcher HELIOSTAR 76 H-alpha Solar Telescope combines a 76 mm aperture with a 630 mm focal length, providing an f/8.3 focal ratio.

Its bandwidth of less than 0.5 Å provides highly selective observation around the hydrogen H-alpha line at 656.28 nm, allowing solar phenomena visible at this wavelength, including prominences, to be observed.

H-alpha Filtration Below 0.5 Å

The optical system uses a combination of front and rear filters to select monochromatic light corresponding to the H-alpha line while blocking other wavelengths.

With a bandwidth below 0.5 Å, the HELIOSTAR 76 H-alpha provides highly selective solar observation around 656.28 nm.

Protection Against Unwanted Radiation

Sky-Watcher incorporates several filtering technologies designed to protect the observer during solar viewing.

The system includes an infrared thermal reflection coating, a dedicated heat-blocking filter and a filter preventing ultraviolet radiation from entering the optical system.

The permanently installed solar filters meet the transmission requirements of ISO 12312-2 for direct observation of the Sun.

Adjustable Etalon

The H-alpha system incorporates an adjustable etalon allowing the solar image to be fine-tuned for optimum contrast on the observed structures.

The Sky-Watcher manual specifies fine adjustment using the control located on the telescope body after focusing.

Integrated Solar Guider

The HELIOSTAR 76 H-alpha incorporates a solar guider allowing the telescope to be aligned with the Sun without looking directly towards it.

The system uses a projected reference and shadow position to progressively centre the telescope on the solar disk.

Focusing

A focusing control at the rear of the optical tube allows the image to be brought into focus before fine adjustment of the etalon.

The telescope also includes a dedicated solar diagonal for observation.

Thermal Stabilisation

Sky-Watcher recommends placing the HELIOSTAR 76 H-alpha outdoors for more than 30 minutes before use.

This allows the temperature inside the etalon compartment to equalise with the outside temperature, providing improved observing and imaging conditions.

6 mm Solar Image at the Focal Plane

With its 630 mm focal length, the HELIOSTAR 76 H-alpha produces a solar image approximately 6 mm in diameter at the focal plane.

This value is specified directly by Sky-Watcher.

Designed for Solar Observation and Imaging

With a 76 mm aperture, bandwidth below 0.5 Å and a weight of 3.8 kg, the HELIOSTAR 76 H-alpha is dedicated exclusively to observing and imaging the Sun in the H-alpha wavelength.

The optical tube is equipped with tube rings and a dovetail for installation on a compatible mount.

Technical Specifications

• Manufacturer : Sky-Watcher

• Model : HELIOSTAR-76Hα

• Type : H-alpha solar telescope

• Aperture : 76 mm

• Focal length : 630 mm

• Focal ratio : f/8.3

• Bandwidth : less than 0.5 Å

• H-alpha wavelength : 656.28 nm

• Solar image size at focal plane : 6 mm

• Weight : 3.8 kg

• H-alpha system : adjustable etalon

• Infrared protection : yes

• Thermal protection : yes

• Ultraviolet protection : yes

• Solar guider : integrated

• Solar diagonal : supplied

• Tube rings : included

• Dovetail : included

• Permanent solar filter compliance : ISO 12312-2 transmission requirements

Package Contents

• Sky-Watcher HELIOSTAR 76 H-alpha solar telescope

• Solar diagonal

• 20 mm 70° wide-angle eyepiece

• Smartphone adapter

• 2.5 mm Allen key

• 5 mm Allen key