Lunt LS50 THa Solar Telescope

Lunt Solar Systems announces new H-alpha solar telescopes, with 50mm free aperture and air-pressure tuning system „Pressure Tuner”!

These compact telescopes will provide 350mm focal length and <0.75 Angstrom bandwidth. Two different versions are available, with B400 blocking filter or larger B600 blocking filter.

Also double-stacking with a bandwidth of only <0.5 Angstrom will be possible with these telescopes.

Therefore a special LS50C filter with compact housing will be available as an additional accessory.

These new telescopes will be available in July / August 2014.

The refractor based telescopes will provide:

- 50mm free aperture (no central obstruction)

- 350mm focal length

- internal Etalon with air-pressure tuning system “Pressure Tuner”

- bandwidth <0.75 Angstrom

- non-rotating Helical focuser

- clamshell with 1/4-20 tapped base (standard thread for photo-tripods)

Lunt LS60 Tha Solar Telescope

The LS60/Ha is a complete Solar Telescope. The refractor based system has a precision aligned singlet chromatical lens with a 60mm aperture. The front singlet lens reduce half the straylight of an achromat , fully eleminate the possibility for on axis coma, astigmatism, decentering aberrations and provides with the matched collimation lens set a full spherical corrected flat-field Solar-Telescope. The focal length is 500mm providing a ~4.5 mm image thru a 6mm blocking filter. Fine adjustment is achieved with a Crayford style focuser or feather touch focuser with 10:1 reduction standard. An internal etalon with tune adjustment allows for a <0.8 Angstrom bandpass.

**Delivery is typically 3 to 4 weeks**

**Please enquire for Double Stack prices and delivery times**

Lunt LS80 THa Solar Telescope

The Lunt H-alpha Solar Telescope with 80mm aperture and <0.7 Angstrom bandwidth. Comes complete with new air-pressure tuning system, zoom eyepiece, and Sol-Searcher.

The LS80THa is a precision aligned ED refractor with a fully un-obstructed 80 mm optical aperture and 560 mm focal length. An internal etalon with new air-pressure tuning adjustment allows for a <0.7 Angstrom bandwidth. This "Pressure Tuner" system allows a better Etalon adjustment than other systems. The “Pressure Tuner” system adapted the Etalon to varying altitudes and atmospheric pressures for always optimal performance. Fine adjustment is achieved with a Crayford style focuser with 10:1 reduction.

Like the smaller LS60THa this telescope is available alternatively with different blocking filters (B1200 or B1800), and with standard Crayford or Feather Touch focuser.

What is the „Pressure Tuner“ system?

The air pressure of the atmosphere varies, depending on if you are at sea level or on a mountain. Unfortunately also the sensitive Etalon filter systems respond to these air pressure variations. The wavelength range that is allowed through the filters, shifts as a function of the air pressure. This shifting is indeed minimal, but at bandwidths of less than one Angstrom it is already clearly visible. If the filter is not adjusted precisely to the H-alpha wavelength, the image of the sun through the telescope degrades, prominences and surface details are no longer visible.

Therefore, the Etalon filter systems have to be adjusted to the prevailing air pressure at the observation location. This “Tuning” called adjustment is typically done by a mechanical tilting of the filter. At sizes of a few Angstrom, it is obviously not easy to achieve the exact adjustment by mechanical tilting. And because the filter is no longer perfectly straight in the beam path, but slightly oblique, there may also be optical failures.

The new air-pressure system “Pressure Tuner” by Lunt Solar Systems takes a different path. The Etalon filter will not be tilted to only simulate a balance to the air pressure, but the air pressure in the filter system is in fact adapted by 100 percent to the real 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 but changes the diffractive index of the air in the chamber and thus accomplishes the same tuning expect that it goes around + or - 0.4 Angstrom on either side of the centerline. Therefore, the patent-pending “Pressure Tuner” system from Lunt Solar Systems is also called “True Doppler Tuning”, and it achieves much better results than conventional tuning systems.

Technical Specs:

Technical data:
Aperture: 80 mm (ED refractor, unobstructed)
Focal length: 560 mm
Bandwidth: internal Etalon with <0,7 Angstrom
Tuning: air-pressure tuning system
Focuser: Crayford-style with 10:1 reduction
Weight: 3.7 kg
The telescope is upgradeable with the new DSII double-stack system. The optional DSII is a internal double stack module with "Pressure Tuner", that provides a bandwidth <0.5 Angstrom. In addition to the "Pressure Tuner" has the DSII module the advantage that there are no more Energy-Rejection-Filter installed, unlike front-mounted double-stack filters. The ERF are allready in the telescope. Therefore the sun's image is brighter and prominences can be better observed than with conventional double-stack systems.


Lunt DSII Double Stack System for LS80THa Solar Telescopes

What is the DSII?

Double stacking reduces the bandwidth of a Hydrogen Alpha Solar Telescope and provides a view that includes significantly more detail on the sun’s surface. This combination of two H-alpha filters is called "double-stacking".

Up to now for this purpose it was needed to equip an additional H-alpha front-filter at the objective of an existing H-alpha telescope. With this arrangement it is possible to experience optical errors, like "ghost" images. And it is also very expensive, because of the large diameter of the front Etalon.

The Lunt DSII system is using a different procedure: the second Etalon will be installed directly inside the telescope. Because this second Etalon is not installed at the objective lens, but placed far behind in the light path, it can be much smaller and therefore cheaper. A complete collimating lens set is integrated in the DSII modules, the optical design ensures a perfect image and avoids “ghost” images.

Because the DSII module is designed only for use in LS80THa telescopes, and in these telescopes all necessary energy filters are already installed, the DSII module has no extra energy filters. This will provide a brighter image of the sun than it is typically with other double-stack systems. Therefore prominences, that will normally be very strongly dimmed by double-stacking systems, can be observed clearly and in greater detail.

And finally the DSII modules are equipped with the innovative "Pressure Tuner" system, which enables high-precision tuning.

The installation of the DSII modules inside the telescope is easy and can be made by the user without any problems. There is no need to return the telescopes to the manufacturer.

Lunt Calcium CaK Solar Telescope

Calcium K (Ca-K) Telescopes and Filters are used to study the wavelength of 393.4nm. This emission line is one of 2 that are produced by Calcium just at the edge of the visible spectrum in a layer that is slightly lower and cooler than the layer viewed in Hydrogen-alpha. The emission line displays areas of Super Granulation Cells that are brightest and strongest in areas of high magnetic fields such as sunspot activity and active regions. Having the ability to study the Calcium K and the Hydrogen-alpha line provides important insights into the structure, strength, and depth of these active regions.

The Calcium K line is centered at 393.4nm. This wavelength is considered to be slightly outside the visible spectrum on the UV side. While most people can visually see the violet color of the wavelength, many cannot resolve the contrast due to yellowing of the cornea. People who have had cataract surgery are often able to see considerable detail. But, it is for these reasons that the Ca-K line is typically studied via the use of cameras which are able to provide stunning details.


Lunt 2" Solar Wedge

2" Lunt White Light Solar Wedge for the ultimate in white light solar performance.

2" barrel for professional Solar-Photography and White Light Solar Observation. Includes the full 2" Polarizing Filter Set and ND 3.0 Filter for photo use.

• 2" Lunt White Light Solar Wedge
• 2" ND3 Pre-installed Filter
• Metal Carrying Case
• Die Cut Foam with room for Accessories
• 2" Polarizing Filter Set


Lunt 2" Polarizing Filter for Solar Wedge

2" Polarizing Filter for the Lunt 2" Solar Wedge