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Baader Planetarium Calcium Gen-II 1.25" Ca-K solar imaging filter with LPFC

Baader Planetarium

Baader Planetarium Calcium Gen-II 1.25" Ca-K Solar Imaging Filter

SKU CH-AQ0E-QYCQ0

Calcium Gen-II 1.25" filter isolates 394 nm wavelength for high-contrast solar surface imaging with camera systems

  • Isolates 394 nm wavelength for high-contrast solar surface detail
  • Dielectrically coated, plane-optically polished glass ensures exceptional image clarity
  • 5 nm half-bandwidth delivers precise, consistent solar imaging
  • Designed for photographic use behind an additional solar filter
  • Reveals chromospheric network, supergranulation cells and Ellerman Bombs

Calcium Gen-II 1.25" Ca-K Solar Filter

The Baader Planetarium Calcium Gen-II 1.25" Ca-K Solar Imaging Filter isolates the 394nm wavelength to reveal high-contrast details on the Sun's surface for solar photography. It is designed for camera use only because the human eye cannot safely handle UV radiation at this wavelength. This filter requires an additional solar filter for safe operation.

Dielectrically coated planeoptical glass

The filter uses dielectrically coated, planeoptically polished glass with a 5nm HBW and 394nm CWL to ensure exceptional image clarity and minimal light scatter. Precise wavelength control delivers accurate and consistent solar details during imaging sessions. Optimised light transmission is designed for photographic use behind another solar filter.

1.25" unstacked design with LPFC

The 1.25" unstacked format fits standard focusers and includes LPFC for improved performance. It is optimised for use with monochrome cameras and mirror telescopes for best results. Many lens telescopes can still be used, though unmodified DSLRs may require significantly longer exposure times. The package includes a sheet for additional filtering needs.

Highlights

  • Isolates 394 nm wavelength for high-contrast solar surface detail
  • Dielectrically coated, plane-optically polished glass ensures exceptional image clarity
  • 5 nm half-bandwidth delivers precise, consistent solar imaging
  • Designed for photographic use behind an additional solar filter
  • Reveals chromospheric network, supergranulation cells and Ellerman Bombs

Specifications

No published specifications for this item yet.

Questions about this item

How do I install the 1.25" Ca-K filter and what step is often missed?

Thread the filter into the camera nosepiece or diagonal, then place a full-aperture solar filter in front of the telescope; the extra solar filter is mandatory and is the step most often forgotten.

What maintenance or replacement will the Ca-K filter need later?

The dielectrically coated, plane-optically polished glass is permanent; only occasional gentle cleaning with optical fluid and a lint-free cloth is required, and no internal components wear out.

What limit appears first during sustained solar imaging with the 394 nm filter?

The 5 nm half-bandwidth fixes the spectral passband, so the practical limit is the camera sensor’s UV sensitivity and the exposure length needed to capture detail without saturating the narrow calcium line.

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