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Daystar Quantum Calcium II H-Line Solar Filter - 5Å PE Grade

Daystar Quantum Calcium II H-Line Solar Filter - 5Å PE Grade

by Daystar Filters
SKU DAY-CH5AUNI
CA$19,586.00 - CA$19,586.00
CA$19,586.00
CA$19,586.00 - CA$19,586.00
CA$19,586.00
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  • Targets the Calcium II H-Line Emission
  • Optimized for Visual and Imaging Use
  • Reveals Lower Chromospheric Detail
  • Produces a High-Contrast Violet Image
  • Professional (PE) Grade Optical System
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  • Daystar Quantum Calcium II H-Line Solar Filter - 5Å PE Grade

    The Daystar Quantum Calcium II H-Line Solar Filter is engineered for observers who want to visually experience the sun's lower chromosphere. By specifically targeting the Calcium H-line, this filter produces a higher contrast and more easily visible violet image than traditional K-line filters, making it a superior choice for direct observation and advanced imaging.

    A Visual-First Approach to Calcium Solar Observing

    While most academic solar research has focused on the Calcium K-line, that wavelength (393.3nm) sits below the approximately 400nm end of the visual spectrum and is difficult for the human eye to perceive. Daystar's H-Line filter targets a different emission line of Calcium that is significantly closer to the visible spectrum, resulting in a bright, high-contrast violet view that is far easier to focus and observe directly through the eyepiece.

    High-Contrast Views of the Lower Chromosphere

    This filter opens a window into the dynamic lower layers of the solar atmosphere, revealing details invisible in white light or Hydrogen-alpha. You can observe the bright, complex magnetic regions known as plage that surround sunspot groups, track the boundaries of supergranulation cells across the solar disk, and witness the energetic brightening that precedes a solar flare.

    Calcium H-Line vs. K-Line: A Comparison for Observers

    The choice between a Calcium H-line and K-line filter comes down to your primary application: research or visual astronomy.

    • Calcium K-Line: This is the traditional choice for university-level research. Its wavelength is well-isolated from other spectral lines, providing clean data for academic studies. However, its wavelength just below the visual spectrum makes it much harder to use visually.
    • Calcium H-Line (This Filter): This filter is designed for the amateur astronomer. By shifting to a wavelength much closer to what the eye can see, it makes direct visual observation of the chromosphere possible and highly rewarding. The view is still a deep violet, but one that your eye can readily focus on, revealing solar features in real-time.

  • What solar features can I see with the Daystar Quantum Calcium II H-Line filter?

    The Daystar Quantum Calcium II H-Line filter reveals features in the sun's lower chromosphere. You will be able to see bright plage (active regions around sunspots), the network pattern of supergranulation cells, and pre-flare brightening in magnetically complex areas.

    Why should I choose this Calcium H-Line filter over a K-Line filter?

    You should choose the H-Line filter if you have any interest in visual observation. The K-line wavelength sits below the approximately 400nm end of the visual spectrum, so it is harder for the human eye to see. The H-line is much closer to the visible spectrum, producing a distinct violet image that is significantly easier to see and focus through an eyepiece.

    Is the Daystar Quantum filter better for visual observing or imaging?

    It is designed to excel at both. However, its primary advantage over traditional K-line filters is its superior performance for visual observation. For imagers, the more visible wavelength can also make achieving sharp focus easier before starting a capture sequence.

    How would the Daystar Quantum Calcium II H-Line filter show a large sunspot group with my 100mm refractor?

    While the sunspots themselves will appear as dark umbra (similar to white light), the Daystar Quantum Calcium II H-Line filter will reveal the extensive, bright, and detailed plage surrounding the spot group. This highlights the intense magnetic activity below the surface, which is completely invisible without a specialized filter like this one.

    Is the Daystar Quantum Calcium II H-Line filter a good choice for my SCT?

    It can be, set up to Daystar's requirements. Calcium H and K filters do not require F/30 but are used at F/15, F/20 or greater, so an SCT must be configured to deliver at least F/15. Instead of a red or yellow glass energy rejection filter, use a dielectric "hot mirror" UV/IR cut filter ahead of focus, plus an additional neutral density solar film on apertures above 150mm or for long-term dedicated use. The brighter, more visible image produced by the H-line can be an advantage on long focal-ratio instruments like SCTs, potentially allowing for shorter exposure times during imaging compared to K-line systems.

    What color is the sun through the Daystar Quantum Calcium II H-Line filter?

    The sun will appear as a high-contrast, deep violet image. This color is the natural result of isolating the specific Calcium H-line emission. While deep, this particular shade of violet is much easier for the human eye to perceive than the light from a K-line filter.

  • Wavelength 396.9 nm (3969 Å)
    Bandpass 5 Å
    Tuning Red/blue wing shift buttons with LCD wavelength readout (0.1 Å)

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