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Lunt LS40THa H-Alpha Solar Telescope - Standard Kit

Lunt LS40THa H-Alpha Solar Telescope - Standard Kit

par Lunt Solar Systems
UGC LSS-LS40THa-Standard-V1
$995.00 - $995.00
$995.00
$995.00 - $995.00
$995.00
Égalisation de prix!
  • 40mm Aperture Dedicated Hydrogen-Alpha Solar Telescope
  • ≤0.65Å Bandpass Front-Mounted Tilt-Tuned Etalon
  • 6mm (B600) Blocking Filter for Visual and Imaging Use
  • Tele Vue Sol Searcher Solar Finder for Safe Aiming
  • Includes 12mm Eyepiece and Hard-Sided Carry Case
  • 400mm Focal Length (f/10)
1 en stock
Expédition internationale
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Manual
  • Warranty

  • Enter the Chromosphere: The Lunt LS40THa Solar Telescope

    The Lunt LS40THa H-Alpha Solar Telescope is a complete, dedicated instrument designed to reveal the dynamic, ever-changing chromosphere of our sun. By combining a 40mm objective with a high-contrast, tilt-tuned etalon, this telescope delivers a direct, unfiltered view of solar prominences, filaments, and surface granulation, all in the brilliant crimson light of hydrogen-alpha.

    This is the ideal starting point for any observer curious about dedicated solar astronomy. Its grab-and-go portability makes it a perfect companion for quick daytime sessions, while its optical system is engineered to provide a level of detail that generic white-light filters simply cannot resolve. With the LS40THa, you are not just looking at the sun; you are watching the active, violent weather of a star in real time.

    A Matched 40mm f/10 Optical System

    The foundation of the LS40THa is its 40mm singlet objective lens, operating at a focal ratio of f/10. This specific focal length is engineered to provide a full-disc image of the sun with ample room around the limb. The f/10 design ensures the light cone presented to the front etalon is nearly parallel, a critical requirement for achieving a uniform, high-contrast image across the entire field of view.

    This aperture provides a perfect balance between resolution and sensitivity to atmospheric seeing. On days of average or poor seeing, a 40mm aperture often delivers a steadier, more pleasing view than a larger instrument, which can be over-magnified for the conditions. This makes the LS40THa a reliable performer, delivering consistent, satisfying views even when the atmosphere is turbulent.

    High-Contrast Tilt-Tuned Etalon with ≤0.65Å Bandpass

    At the heart of the LS40THa is its front-mounted, tilt-tuned Fabry-Pérot etalon. This precision filter isolates a narrow slice of the solar spectrum at the 656.28nm Hydrogen-alpha line, with a full-width half-maximum (FWHM) bandpass of ≤0.65Å. This narrow bandpass is essential for rejecting the overwhelming glare of the photosphere, allowing the faint, low-contrast structures of the chromosphere to become visible.

    The simple and robust tilt-tuning mechanism allows you to shift the filter's bandpass slightly off the central H-alpha line. This control is vital for observing features that are Doppler-shifted due to their velocity, such as solar flares or fast-moving plasma in active regions. A slight turn of the tuning wheel can make a faint filament snap into sharp relief against the solar surface.

    The B600 Blocking Filter

    The etalon works in concert with the B600 blocking filter, housed within the 90-degree star diagonal. The "B600" designation refers to its 6mm internal aperture, which is sized to pass the full solar disc from the 400mm focal length optical tube. This filter serves as the final, critical stage of the safety system, eliminating all out-of-band wavelengths and providing the observer with a purely monochromatic image.

    The 6mm aperture of the B600 provides a generous field of view around the solar disc and is well suited for both visual observation and solar imaging. Whether you want to frame the entire sun and its surrounding prominences in a single view or capture high-resolution images of active regions and filaments, the B600 delivers a bright, high-fidelity image perfectly matched to the telescope's focal length.

    Simple and Precise Helical Focuser

    Focusing on the sun requires small, deliberate adjustments, and the LS40THa's helical focuser is designed for this task. Unlike a rack-and-pinion focuser, a helical mechanism moves the eyepiece in and out with a simple rotation of the barrel. This design is compact, mechanically simple, and prevents any image shift during focusing.

    The non-rotating action is a key benefit. It ensures that your eyepiece, or a camera if you are imaging, maintains its orientation as you fine-tune the focus. This makes it easier to keep your target framed and simplifies the process of achieving the sharpest possible view of delicate filamentary structures or the fine spicules at the solar limb.

    Safe and Fast Targeting with the Tele Vue Sol Searcher

    Aiming a telescope directly at the sun is inherently dangerous without a proper finder. The LS40THa includes the Tele Vue Sol Searcher for safe, precise solar acquisition. This is not an optical finder you look through; instead, it projects a small shadow or dot onto a small, white target screen, allowing you to center the sun without ever looking toward it.

    To use it, you simply move the telescope tube until the indicator is centered on the target. This process is completely safe, intuitive, and takes only a few seconds. It eliminates any guesswork and ensures you can acquire and center the sun in the eyepiece quickly and confidently, getting you observing faster.

    Mounting and Experiencing the View

    The included 4-inch Vixen-style dovetail bar makes the LS40THa compatible with a wide range of lightweight, portable astronomical mounts. It can be easily carried by a photo tripod with a fluid head or any entry-level equatorial or alt-azimuth mount, making it an excellent "grab-and-go" instrument.

    With the included 12mm eyepiece, the telescope operates at 33x magnification. At this power, the entire solar disc is framed comfortably in the field of view. As your eye settles, you will first notice the sharp, well-defined limb. With a slight adjustment of the tilt-tuner, you will see immense prominences, appearing like ghostly red flames erupting from the edge. On the surface itself, dark, snaking filaments and bright, active regions (plage) become apparent, changing day by day.

    Trade-Offs and Upgrade Path

    The primary trade-off for the LS40THa's portability and price is its aperture. While 40mm provides excellent full-disc views, it has a lower resolution ceiling than larger instruments like the LS60MT or LS80MT for observing fine surface detail. Its tilt-tuned etalon is also more susceptible to off-band transmission at the edge of the field compared to Lunt's internal pressure-tuned systems, though this is rarely an issue for visual observation.

    However, the LS40THa offers a powerful upgrade path. By adding the LS40FHa front-mounted double-stack filter (sold separately), you can dramatically increase contrast on surface features, making the solar disc appear almost three-dimensional. This allows the telescope to grow with your interest in solar astronomy.

  • Is the Lunt LS40THa safe to use for solar observing?

    Yes. It is a dedicated solar telescope with a multi-stage filtering system, including a front etalon and a rear blocking filter. It is engineered from the ground up for safe solar observation. You should never use a standard nighttime telescope with a simple front filter to view the sun.

    What will I actually see with the LS40THa telescope?

    You will see the sun's chromosphere in the red hydrogen-alpha wavelength. This includes solar prominences (eruptions on the edge), filaments (dark ribbons on the surface), active regions (bright areas called plage), and surface granulation.

    How does the LS40THa compare to the Lunt LS50THa?

    The LS50THa has a larger 50mm aperture, which provides slightly higher resolution on surface details under good seeing conditions. The LS40THa is smaller, lighter, and more affordable, making it a better choice for portability and as an entry point into solar astronomy.

    What kind of mount do I need for the Lunt LS40THa?

    The LS40THa is very lightweight and will perform well on a sturdy photo tripod with a fluid video head. For better tracking and slow-motion control, an astronomical mount like the Sky-Watcher AZ-GTe or a Celestron NexStar SLT is recommended.

    Can I take pictures of the sun with this telescope?

    Yes, solar imaging is fully supported. You can use a dedicated astronomy camera or even a smartphone with an appropriate adapter. The B600 blocking filter's 6mm aperture is well suited for both visual use and imaging, delivering a bright, high-fidelity image across the full solar disc.

    What is the purpose of the "double-stack" filter upgrade?

    Adding a second etalon (double-stacking) dramatically increases contrast on surface features like filaments and granulation, making them appear more detailed and pronounced. It has less effect on prominences at the limb.

  • Telescope Type Dedicated H-Alpha Solar Telescope
    Aperture 40 mm
    Focal Length 400 mm
    Focal Ratio f/10
    Etalon Internal, Tilt-Tuned
    Bandpass <0.65 Ångström
    Blocking Filter B600 (6mm)
    Focuser Helical Focuser
    Mounting 4" Vixen-Style Dovetail
    Weight 3 lbs (1.36 kg)
    Storage Aluminum Hard Case with Custom Foam

    • LS40THa H-Alpha Telescope

      × 1

    • B600 Blocking Filter in Diagonal

      × 1

    • Helical Focuser

      × 1

    • Tele Vue Sol Searcher Solar Finder

      × 1

    • 4" Vixen-Style Dovetail Bar

      × 1

    • 12mm Solar Eyepiece

      × 1

    • Hard-Sided Carry Case with Custom Foam

      × 1

  • Lunt Solar Systems 5-Year Warranty