Cloud Break Optics

Calcium-K Module

Calcium-K Module - Main image
$662.3 $895 In stock

Category: Solar Filters

All sales of solar gear are final, so please choose your filter carefully and reach out with any questions.

PRODUCT DESCRIPTION

Calcium K (Ca-K) telescopes and filters are used to study the wavelength of 393.4 nm. This emission line is one of two 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 393.4 nm. 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.

Internal narrowband filters allow for a <2.4 Angstrom bandpass. This is primarily an imaging system due to the difficulty of many to visually see everything that CaK has to offer.

Choose the best CaK Module for your Telescope Size and Focal Length:

B600:     For telescopes up to 100 mm aperture and 600 mm focal length

B1200:   For telescopes up to 100 mm aperture and 1200 mm focal length

B1800:   For telescopes up to 100 mm aperture and 1800 mm focal length

B3400:   For telescopes up to 100 mm aperture and 3400 mm focal length

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (5.0 / 5 · 5 reviews)

Ryan ★★★★★

Took this Ca-K module out for a quick test on a sunny morning, and the contrast on the solar surface was immediately impressive. The image stays sharp even when I push the magnification a bit. I’m really glad I went with this setup.

Harper ★★★★★

I’ve been using this Ca-K module to track solar activity, and the way it isolates that specific wavelength makes surface details really pop. The narrow bandpass is incredibly precise, delivering sharp, high-contrast views of filaments and plage regions.

George B. ★★★★★

The Ca-K bandpass is incredibly narrow—I’m seeing surface granulation and plage details I never caught with my standard white-light setup. Took a bit to dial in the focus, but the contrast on my 80mm refractor is stunning.