Lunt Solar Systems LS40THa/B1200 H-alpha Solar Telescope

The Lunt LS40THa/B1200 is a dedicated hydrogen-alpha solar telescope designed to provide detailed views of the Sun’s chromosphere. Unlike white-light solar telescopes, which show features such as sunspots on the visible surface of the Sun, an H-alpha telescope uses a very narrow band of light around 656.28 nm to reveal structures and activity in the solar atmosphere.

With its 40mm aperture and 400mm focal length, the LS40THa is a compact and highly portable solar telescope. Its relatively short focal length makes it straightforward to achieve useful magnifications with standard 1.25″ eyepieces, while the small aperture keeps the telescope light and easy to handle.

The telescope uses an internal H-alpha etalon with a specified bandpass of less than 0.7 Å. This narrow bandpass allows the LS40THa to reveal features such as prominences around the edge of the solar disc, as well as filaments, active regions and other chromospheric detail across the face of the Sun.

The H-alpha system uses mechanical tilt tuning, allowing the observer to adjust the etalon to optimise the view of different solar features. This is particularly useful when observing features that appear at slightly different wavelengths because of the motion of material in the solar atmosphere.

The LS40THa/B1200 is supplied with Lunt’s B1200 blocking filter, which has a 12mm clear aperture and is incorporated into the 1.25″ star diagonal. The generous blocking-filter aperture provides a comfortable field for visual observation and also makes the telescope suitable for use with compatible solar imaging equipment.

Focusing is handled by a non-rotating 1.25″ helical focuser, providing straightforward and precise focus adjustment. An integrated Sol-Searcher makes it easy to align the telescope with the Sun without the need for a conventional optical finder.

The telescope is supplied with a GP-level dovetail bar for mounting on a suitable astronomical mount. The dovetail also incorporates a 1/4″-20 mounting thread, allowing the telescope to be used with a compatible photographic tripod.

The LS40THa/B1200 is an excellent choice for anyone looking for a dedicated solar telescope that can be taken outside quickly and used whenever conditions are suitable. Its compact dimensions and low weight make it particularly convenient for regular solar observation, while its narrow H-alpha bandpass opens up an entirely different view of our nearest star.

Important: The LS40THa/B1200 is a dedicated solar telescope and must only be used for solar observation with all supplied solar-filtering components correctly installed. Never attempt to observe the Sun through a telescope unless it is specifically designed and configured for safe solar observation.