Happily Serving You in the Same Location for Over 58 Years!


Lunt - 100mm Ha Telescope w/ Internal Etalon and B3400 Blocking Filter

Model#: LS100THa/B3400

Be the first to review this product

Availability: In stock


Manufactured by: Lunt Solar Systems


The LS100THa/B3400/FT is a complete Solar Telescope. The refractor based system has a precision aligned singlet chromatic lens with a 100 mm aperture. The front singlet lens reduces the stray-light over an achromat by half. With its matched collimation lens set, it also fully corrects on-axis coma, astigmatism and de-centering aberrations and provides a full spherically corrected flat-field Solar-Telescope. The focal length is 714mm providing a ~7.3 mm image thru an included 34mm blocking filter. Coarse focus adjustment is via a slide tube. Focusing is achieved with a high precision 2″ Starlight Instruments FeatherTouch dual speed focuser  10:1 reduction as standard equipment.

An internal etalon with Pressure Tune Adjustment allows for a <0.7 Angstrom bandpass.  The Etalon filter adjustment is NOT  tilted to only simulate a balance to the air pressure, but the air pressure in the filter system will adjust to 100 percent to the actual external air pressure. Thereafter the air surrounding the Etalon can simply be compressed or decompressed by the tuning system in order to change the air pressure between the surfaces. This allows the Etalon surfaces to always remain at the same perfect angle to the light waves.

Lunt Solar Systems'  Doppler  Pressure Tuning method allows the user to rapidly scan the scope’s sub-angstrom passband over the hydrogen alpha wavelength. Simply put, the advanced technology of Doppler True Tuning for fine adjustment of the center wavelength allows research of the Sun’s disk and surface details at increased image scale. Prominences, flares, super granulation, filaments, and active regions will be seen or imaged with amazing precision.  The LS100THa can be internally double stacked (see LS100Ha/PT/DSII) at time of purchase or anytime thereafter which reduces the bandpass to <0.5 Angstroms.  Doublestacking provides a truly enhanced high definition view of the Suns' surface details.  The Scope does not need to be returned to the factory for doublestacking as long as you have the red anodized front cell on your telescope.  If you have an older model (just a white tube with no red) you will need to upgrade the scope before using the internal double stack DSII-LS100T. 

* BLOCKING FILTERS are REQUIRED on all Lunt Solar Telescope Systems *
Lunt Solar Systems currently offers 4 blocking filter apertures for use with our Etalon systems. The Blocking Filter houses additional filters which are required for the safety and performance of the solar package.  Lunt Solar blocking filters contain a unique filter system. Lunt will only warranty safety or performance when a Lunt blocking filter is paired with a Lunt H-alpha filter or telescope.

 Required Blocking Filter:

  • B1200 for standard visual use  (scope focal length up to 1200mm)  optional
  • B1800 for larger field of view - viewing and imaging applications  optional
  • B3400 even  larger field of view viewing and superior imaging use (available only in extension tube or "straight-thru" design) Included


When imaging with a Lunt Solar System it is recommended that the user opt for the next larger Blocking Filter than that recommended for Visual use.  This is due to the fact that most Imaging Systems require additional “backfocus”.  This requires that the Blocking Filter be moved further up the light cone. As a result the aperture of the Blocking filter needs to be larger to allow for the larger cone size.

  • The Lunt Solar Systems LS100THa Hydrogen-Alpha Telescope comes with a precision aligned 100mm singlet chromatical lens. 

  • Internal etalon system with tune adjustment that allows a maximum of <0.75 Angstrom bandpass. The internal module has an optimized collimating system to reduce off axis aberration.

  • This Lunt 100mm Hydrogen-Alpha Telescope has a focal length of 714mm.

  • This model includes a 2" dual speed 10:1 Feathertouch focuser, a clam shell mounting ring, sun finder, B3400 blocking filter, and a foam-lined case.

LS100T Features: (single stacked)

  • Optical Aperture: 100mm
  • Etalon: Internal <0.7 Angstrom
  • Tuning: Internal Pressure Tune (Doppler True Tuning)
  • Focal Length: 800mm
  • F Ratio: F/7
  • Focuser: 2″ Feather-Touch focuser with 10:1 reduction
  • Tube diameter: 121mm
  • Tube length with blocking filter: 634mm
  • Storage: Aluminum finished hard case with fitted foam
  • Weight: 13 lbs


 Included Accessories: 

  • Optical tube with 2″ feather touch focuser with 2.5″ travel,
    includes adapter
  • B3400 Blocking Filter
  • Sun Finder: Televue Sol Searcher
  • Mounting: Lunt 12″ Dovetail
  • Case: Aluminum Finished Hard Case with Custom Foam












Additional Information

Name Lunt - 100mm Ha Telescope w/ Internal Etalon and B3400 Blocking Filter
Manufacturer Lunt Solar Systems
Model LS100THa/B3400
Aperture 100mm
Bandwidth <0.75Å
Bandpass Blocking Filter Lunt diagonal w/ b3400 (34mm)
Barrel diameter 2"
Caps Y
Carrying Case Aluminum
Central obstruction Unobstructed
Collimation Cap Internal collimation lens system
Design Refractor based Solar Dedicated
Etalon Internal with Pressure Tuning
Finderscope TeleVue Sol Searcher Sun Finder
Fine Focus Yes
Focal Length 714mm
Focal Ratio f/7
Focal Tube Travel 2.5"
Focuser FeatherTouch
Focus Assist Dual Speed
Focus System Friction
Mount Lunt Dovetail
Mount Base Size 12"
Objective Precision aligned singlet chromatical
Optical Coatings Multi coatings
Pressure Tuning True Doppler Tuning
Solar Filter Yes
Spectrum centered on 656.28nm
Star Diagonal Lunt w/ blocking filter
Thermal Stability RFG
Warranty 5 yrs
Weight in Use ~13 lbs