Lunt Solar Telescopes and Filter Systems
Lunt Solar System LLC is a Tucson-based company that specialises in the design and manufacture of high-quality solar observation equipment. They make an excellent range of solar telescopes and filter systems with a wide range of options.
Their range spans the entry level LS35 with its 35mm aperture right up to the massive LS230 due for release in the summer of 2011. Most of the range is designed for the hydrogen alpha line but they also make Calcium K systems that operate in the blue part of the spectrum.
We have selected some of the most popular telescopes in the range as the choices can be bewildering, but we can supply any of their products.
How do you choose the right model for you?
Hydrogn Alpha or Calcium K?
The simplest question is hydrogen alpha or Calcium K? For most people the answer will be hydrogen alpha as this red wavelength is easily visible making it suitable for visual observation and imaging. Calcium K is at the limit of the visible spectrum for and is difficult to see, so calcium K telescopes are optimised for imaging and would normally appeal to a specialist.
Size of Aperture?
Size of aperture is closely linked to budget. The wider the aperture the more detail you will see but the price does rise quite steeply.
Size of Blocking Filter?
The heart of the solar telescope is the Fabry-Perot etalon, a very accurate filter requiring the highest manufacturing quality. It works in conjunction with a blocking filter that helps determine the size of the image plane. Small blocking filters are usually fine for visual use but larger ones are needed for imaging, especially with large CCDs. We try to indicate which blocking filter to choose for your application.
Single Stack or Double Stack?
Basic solar telescopes use a single Fabry-Perot etalon which produces a pass band around 0.7 angstroms. This narrow band is essential to cut out the glare of the solar spectrum and isolate the wavelength that shows prominences and other interesting features. Double stacking means using two etalons in series to reduce the band pass to less than half an angstrom. Even greater detail is revealed by the narrower pass band.
What about pressure tuning? Because the pass band of a solar telescope is so narrow it is essential that it is positioned accurately around the wavelength of interest. Mechanical tuning is used in most solar telescopes but Lunt also offer the option of pressure tuning which gives more precise control.
Is a Feathertouch focuser necessary?
Lunt solar telescopes are supplied as standard with a quality Crayford focuser but more precise focus control can be achieved using a Feathertouch focuser. These are popular with dedicated imagers.
What about options not listed on the web site?
We can supply all the Lunt models with other options including double-stack etalons. Please call us for details and prices.