Antlia 1.25" Calcium K-Line 3nm Filter

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Antlia's CaK 393.3nm 1.25" mounted solar filter is made of heat resistant double-polished substrate and uses the most advanced multicoatings to produce a sharp 3nm narrow bandpass. Designed to maximize contrast for high-resolution imaging of sun spots, plage, solar surface granulation and other features that are prominent in CaK light.
With a density of OD5 (0.001%) between 200-1200nm wavelengths and OD3 (0.1%) between 1200-1500nm wavelengths, the Antlia CaK 3nm filter delivers superb resolution for imaging. It should be noted with a bandpass for CaK (393nm), solar features are almost invisible to human vision because of the eye's low UV sensitivity. The Antlia Solar Wedge with CaK filter is not recommended for visual observation. It is designed for imaging with cameras that have spectral responses well beyond human vision.
Never look into the sun with the K-Line filter alone, although you won't perceive it, there is a lot of harmful UV radiation entering your eye.
Please note that the CaK 3nm 393.3nm filter is screwed into the Antlia Herschel Wedge Prism. You do not need to buy it separately if you use the Herschel Wedge Prism.
Other Information
- Country of Manufacture: China
Antlia's CaK 393.3nm 1.25" mounted solar filter is made of heat resistant double-polished substrate and uses the most advanced multicoatings to produce a sharp 3nm narrow bandpass. Designed to maximize contrast for high-resolution imaging of sun spots, plage, solar surface granulation and other features that are prominent in CaK light.
With a density of OD5 (0.001%) between 200-1200nm wavelengths and OD3 (0.1%) between 1200-1500nm wavelengths, the Antlia CaK 3nm filter delivers superb resolution for imaging. It should be noted with a bandpass for CaK (393nm), solar features are almost invisible to human vision because of the eye's low UV sensitivity. The Antlia Solar Wedge with CaK filter is not recommended for visual observation. It is designed for imaging with cameras that have spectral responses well beyond human vision.
Never look into the sun with the K-Line filter alone, although you won't perceive it, there is a lot of harmful UV radiation entering your eye.
Please note that the CaK 3nm 393.3nm filter is screwed into the Antlia Herschel Wedge Prism. You do not need to buy it separately if you use the Herschel Wedge Prism.
Antlia's CaK 393.3nm 1.25" mounted solar filter is made of heat resistant double-polished substrate and uses the most advanced multicoatings to produce a sharp 3nm narrow bandpass. Designed to maximize contrast for high-resolution imaging of sun spots, plage, solar surface granulation and other features that are prominent in CaK light.
With a density of OD5 (0.001%) between 200-1200nm wavelengths and OD3 (0.1%) between 1200-1500nm wavelengths, the Antlia CaK 3nm filter delivers superb resolution for imaging. It should be noted with a bandpass for CaK (393nm), solar features are almost invisible to human vision because of the eye's low UV sensitivity. The Antlia Solar Wedge with CaK filter is not recommended for visual observation. It is designed for imaging with cameras that have spectral responses well beyond human vision.
Never look into the sun with the K-Line filter alone, although you won't perceive it, there is a lot of harmful UV radiation entering your eye.
Please note that the CaK 3nm 393.3nm filter is screwed into the Antlia Herschel Wedge Prism. You do not need to buy it separately if you use the Herschel Wedge Prism.
Other Information
- Country of Manufacture: China
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Antlia 1.25" Calcium K-Line 3nm Filter


















