Designed and purpose-built for solar observation, the Lunt Solar Systems LS100THa 102mm f/7 Refractor Solar Telescope features a large 102mm objective lens and an internal etalon with a <0.7 Angstrom bandpass. To use this scope properly and safely, it must be used with a rear eyepiece blocking filter. It is being offered here without a blocking filter for users who already have one..
Integrating the etalon into the optical path reduces interference and distortion which can occur with externally mounted filters. Its singlet chromatic lens reduces the stray light over an achromat lens by half, and the matched collimation lens set fully corrects on-axis coma, astigmatism and de-centering aberrations, and provides a spherically corrected flat-field view. True Doppler Tuning allows for a shift into and away from the user for a richer depth of field. While looking at a filament at the center of the Sun, the user has the ability to Doppler shift from the base of the filament to the tip, following the filament through its structure toward and away from them, allowing for enhanced visual and imaging capability.
Complementing the optical performance and technologies is a patented StarLight Instruments 2" FeatherTouch reverse-Crayford dual-speed focuser. This innovative design improves on the standard Crayford through the use of a bearing system to increase the focusing mechanism's contact points to increase load capacities, improve precision, eliminate focus backlash and vibrations. The bearings also require much less torque to move the drawtube forward and back, needing only a feather-light touch.
To safely find the Sun in preparation for observing, Lunt includes the Tele Vue Sol-Searcher solar finderscope. With the Sol-Searcher, unlike conventional finderscopes, the Sun shines through a small aperture in the front and projects an image on an opaque screen. When the image on the screen is centered, the Sun should be centered in the eyepiece making it a safe and easy way to locate the Sun without having to look at it unprotected. This solar scope is offered here without a mount or tripod and comes equipped with a 12" Vixen/Losmandy-style dovetail plate that enables it to be mounted on any compatible platform. A foam-lined aluminum hard carrying case is included for safe and secure transport and storage.