Antlia Solar Discover 5Å CaK filter

Antlia Solar Discover 5ÅCaK

The Antlia Solar Discover 5Å CaK is a specialized optical system for solar imaging, incorporating light-reduction filters to limit the influx of solar heat and improve safety during use. Designed to maximize the contrast of sunspots, light bridges, and solar features on the Calcium II K line (393.3 nm), it offers an ultra-narrow bandwidth of 0.5 nm to capture fine details of the solar chromosphere.

Key features

• Integrated filter: ultra-narrow bandwidth 5Å (0.5nm) centered on 393.3nm
• Clear aperture: D12mm (B1200)
• Fully enclosed tube in CNC aerospace aluminum, preventing light leakage
• Effective reduction of heat input for safe solar imaging
• Installation similar to the Herschel CaK 3nm prism

Compatibility and Accessories

• For use with telescopes with focal ratio > f/7 without Barlow
• Barlow 2X, 3X, and 5X for Solar Discover 5Å CaK (optional)
• Adjustable aperture diaphragm, 2.0 mm–25 mm (optional)
• Focal length extensions: 50mm and 70mm tubes available as options
• Secure installation required with an additional ERF for lenses with an aperture > 100 mm

Important notes

• Without an additional light-reducing device; limited to refracting telescopes with apertures up to 100 mm
• Requirement to use an ERF when using zenith mirrors or Barlow lenses from other brands
• Correct installation essential for safe operation

Visual use

The CaK band (393.3 nm) is nearly invisible to the human eye. The Solar Discover 5Å CaK is designed primarily for imaging and is not recommended for visual observation. Furthermore, the IR coverage of the filters does not exactly comply with ISO 12312-2 standards. Any visual use must be done with extreme caution and only if the filters are in perfect condition.

Compliance with ISO standards

• Tmax% (380-780nm): 0.0032%
• Tmin% (380-780nm): 0.000061%
• Tmax% UVB (280-315nm): 0.0032%
• Tmax% UVA (315-380nm): 0.0032%
• Tmax% IR (780-1700nm): 3%

Solar Discover options (select from drop-down menu)

• Solar Discover 5Å CaK Assembly alone: USD 880
• Solar Discover 5Å CaK with Barlow 2X or 3X: 930 USD
• Solar Discover 5Å CaK with Barlow 5X: 940 USD
• Barlow 2X or 3X alone: USD 50
• Barlow 5X alone: USD 60
• Adjustable diaphragm: USD 50
• 50mm extension: USD 20
• 70mm extension: USD 25

Warranty

• 3-year manufacturer's warranty
• Any disassembly of the unit will void the warranty.
• No repair, return or exchange possible in case of disassembly

Safety precautions

• Never use without an appropriate light reduction system for apertures >100mm.
• Prohibited for unsecured visual observation of the Sun.
• Always check that the filters are intact before use.