Lunt LS60MT H-Alpha Solar Telescope - Premium PLUS Kit

The 60mm F/7 ED Doublet Optical Tube

At the heart of the LS60MT is a 70mm f/6 FLP51 ED doublet objective lens, of which 60mm (f/7) is used in H-alpha. The 60mm aperture provides a significant increase in resolving power over smaller 40mm and 50mm solar telescopes, rendering finer detail in the wispy texture of prominences. The use of Extra-low Dispersion (ED) glass minimizes chromatic aberration, which is critical not only for its nighttime performance but for ensuring the highest possible contrast at the focused H-alpha wavelength.

This aperture is a carefully considered choice. It is large enough to resolve fine chromospheric detail yet small enough to remain largely immune to the effects of daytime atmospheric seeing. This results in more frequent opportunities for high-magnification observing compared to larger solar telescopes, which are often limited by local atmospheric turbulence.

Internal Pressure-Tuned Etalon for Uniformity

The primary filtering is performed by an internal, unobstructed etalon. Unlike front-mounted filters, this internal placement protects the most critical optical component from the elements. Lunt's Doppler True Tuning system uses air pressure to adjust the etalon's bandpass, a method that avoids the mechanical stress and potential tilting inaccuracies of other tuning systems. This ensures a uniform, on-band image across the entire field of view, free from hot spots or gradients.

The observer's benefit is direct and immediate. As you adjust the pressure, you can shift the filter's bandpass slightly off the central H-alpha line. This allows you to track the Doppler-shifted motion of plasma in solar flares and active regions, adding a dynamic, real-time dimension to your observation that a static filter cannot provide.

Double-Stack Etalon for Maximum Surface Contrast

This Premium PLUS kit includes the matching LS50FHa front-mounted etalon, which works in series with the internal filter. This "double-stacking" dramatically narrows the final bandpass from a standard ≤0.45Å down to a very narrow <0.28Å. This reduction is the key to unlocking the highest-contrast views of the solar chromosphere.

The visual effect is a significant darkening of the solar disk, which causes surface features like plage and filaments to stand out with pronounced definition. While a single-stacked view is excellent for prominences at the solar limb, the double-stacked view reveals the intricate, web-like structure of the chromosphere itself. For the dedicated solar observer, this enhanced contrast is not a luxury, it is the primary goal.

The B1200 Blocking Filter Advantage

The blocking filter is the final, essential stage in any dedicated solar telescope. This kit includes the upgraded B1200, which offers a 12mm aperture. This larger filter provides a wider, fully illuminated field of view compared to the standard B600, making it a better match for imaging with cameras that use larger sensors.

Even for visual observers, the B1200 provides more generous eye placement and a more comfortable view when using wide-field, low-power eyepieces. It ensures that the edges of the field are not dimmed or vignetted, preserving the quality of the view from the center to the edge of the field stop.

Robust 2" Rack & Pinion Focuser

The LS60MT is equipped with a 2-inch rack and pinion focuser. This design is more robust than a helical focuser, providing the rigidity needed to support heavier eyepieces, Barlow lenses, or imaging cameras without slipping or flexing. The coarse and fine focus knobs allow for quick initial focusing followed by the precise adjustments needed to resolve delicate solar features.

This choice of focuser is a practical one. It simplifies the process of switching between visual observation and imaging, and its non-rotating design means your camera orientation stays fixed as you focus, eliminating the need to re-frame your target after each adjustment.

Modular Design for Day and Night Versatility

The "MT" designation stands for Modular Telescope, a key feature of this system. The H-alpha module containing the etalon can be easily removed, and the 70mm f/6 ED refractor can be used as a conventional telescope for nighttime astronomy or daytime terrestrial viewing. This dual-purpose capability represents a significant value.

This is the system for an observer who wants one high-quality, portable refractor to do it all. You can spend the day observing the Sun in high-resolution H-alpha, and then, in minutes, convert the scope to view the Moon, planets, or star clusters at night. It is a true grab-and-go instrument for any time of day.

The Double-Stacked Solar Experience

With the zoom eyepiece included in this kit, center a large, arching prominence on the limb of the Sun at low power. Now increase the magnification. With the double-stack engaged, the prominence resolves into fine, feathery strands of plasma against a truly black sky. Now move your view onto the solar disk itself and focus on a long, dark filament snaking across the surface. The <0.28Å bandpass makes the filament appear almost three-dimensional, a dark river of cooler hydrogen suspended over the brighter, churning chromosphere below. This is the view that dedicated solar telescopes are built to deliver, and it is a sight that never gets old.