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Solar Spectrum Suna (25mm clear aperture)

Original price $2,390.00 - Original price $2,390.00
Original price
$2,390.00 - $2,390.00
Current price $2,390.00
Version: 0.65 +/- 0.1 Angström

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  • 25mm Clear Aperture
  • HW of 0.65Ang +/- 0.1Ang gives best performance for both Disk and Prominences
  • Tiltable Etalon
  • TEC Oven with controller
  • Compact Form Factor
  • Compatible with all Solar Spectrum and Baader H-a adapters and accessories

The new Suna is Solar Spectrum’s first tiltable temperature controlled H-alpha filter.  The tilt function enables rapid tuning and quick wavelength changes for Doppler observing.  Unlike simpler systems, the thermoelectric oven can heat or cool, so it is able to keep the filter precisely on-band even in hot or cold environments.

Suna also incorporates a compact round form-factor housing.  Unlike all-in-one solutions with smaller aperture and no ability to adjust the focal ratio, the Suna is fully configurable.  Its full-featured design maintains modularity and compatibility with all the Baader H-a accessories and telecentric lenses.   It’s ideal for the amateur looking to get into serious H-a viewing on a budget, and grow with them without compromising performance or capabilities.

Solar Spectrum produces what we have found to be the ultimate in high resolution H-Alpha filter systems. With over 30 years of experience in making filter systems for professionals as well as amateurs, Solar Spectrum brings an unmatched level of expertise to bear in producing filters at prices accessible to amateurs. This experience uniquely enables them to deliver a high level of quality and consistency in very narrow filters (< 0.3A) which are extremely demanding to produce.

These rear-mounted mica etalons deliver high-quality narrowband filtration that can be used with apertures from as small as 40mm up to 180mm! Unlike front objective etalons, the telescope aperture is not limited by the diameter of the etalon.  Every Solar Spectrum filter can be flexibly configured to match any desired telescope and aperture desired, without any loss in resolution. Each Solar Spectrum Suna filter system includes the rear mounted etalon assembly (which includes an integrated thermoelectric heater/cooler), temperature control box, Power Supply, and AC power cable. The control box accepts 90-256 VAC 50/60Hz. For DC use, any inexpensive inverter can be used. A complete system consists of a Solar Spectrum Filter and Front-Mounted Energy Rejection Filter. Telescopes with focal ratios faster than f/20 will also require a telecentric lens to produce the desired f/25 - f/30 beam. Currently, Telecentric lenses are available in 2X, 3X, and 4X amplifications.

Important note: Requires an additional Energy Rejection Filter (D-ERF) in front of the lens.

Availability: Currently, we offer Solar Spectrum filters on a special order basis. Typical delivery times range from 12-24 weeks, depending on filter size and bandpass. Occasionally we will have a system available from stock. Please contact us for specifics. Narrower bandpasses available on request (primarily for imaging use). Calcium K-Line and custom filters are also available upon request.

Payment: Deposit of 50% required at time of order, remainder due when filter is completed and ready to ship. Payments by check or money order only (sorry, no paypal or credit cards for Solar Spectrum Products).


Solar Spectrum H-alpha-filter and Telecentric Systems - Application and Tips