Baader K-Line filter 1.25" for solar photography in calcium light
Very clear imaging of flare areas in the deep blue spectral portion of sunlight.
Baader Calcium Solar FilterThe 1.25" filter for digital cameras and webcams to photograph the calcium line of the solar spectrum. The filter shows the two lines at 393 nm and 396 nm. This gives a deep blue image. The filter is especially suitable for Newtonian telescopes. A refractor should have a good correction in the blue spectrum.
This is a calcium filter for photographing the boundary layer between photosphere and chromosphere. Due to a special coating technology and lower half-width, no filter stacking is necessary!
With this Baader Gen II calcium filter, Baader has succeeded in offering the advantages of previous filters at a lower price. So the "blue sun" is now accessible to more observers than ever before.
What does the photo show?In the light of the calcium lines a region of the sun becomes visible, which lies between the photosphere, which can be observed in white light, and the chromosphere visible in H-alpha light. Flares are scattered over the entire surface of the Sun, and bright zones and a condensed flare network are visible around groups of spots.

Direct comparison of the images to the Solar Continuum, which already offers a significant increase in contrast. The flare areas are clearly visible.
The
photographic solar filter film from Baader is necessary for light attenuation. Included is a 20x25 cm piece, from which you can build your own solar filter. Alternatively, we also offer ready-made solar filters with robust aluminum mounts. When ordering such a filter through the store, please specify that the filter should be equipped with the
photographic film. The visual film (16x denser) would darken the image of the sun too much.
For refractors without correctors, you can also use a Herschel wedge instead of the film, whereby the often built-in ND3.0 filter may have to be replaced by an ND1.8 filter.
Important Observation NoteThe calcium line is very close to the UV range which is harmful to eyes, so we do not recommend visual use. Eye damage may result. Photography, on the other hand, is harmless.