Baader Calcium K-Line Filter.

The New Baader Planetarium Calcium K-Line Filter makes imaging of the sun in K-Line
accessible to anyone with a telescope and digital camera or webcam. Baader's innovative
double-stacked filter uses sophisticated coatings to produce a sharp 8nm wide bandpass,
centered at 395nm. This bandpass provides ample contrast for high-resolution imaging of
super granulation, flares, and other features that are prominent in CaK. Unlike small,
dedicated, and expensive CaK telescopes, the Baader K-Line filter works with with your
existing telescope - at a small fraction of the cost. The Baader CaK may be used with
virtually any telescope, of any aperture - Newtonian, SCT, Refractor, etc.

The Baader K-Line Filter is simply used just like any standard 1.25" thread-on eyepiece filter.

It may be attached to an eyepiece for projection imaging (see Digital Photography for camera
projection adapters and Digital T-Rings), or directly to a camera's nosepiece (ie, T2-14) for
prime-focus. In addition, an objective pre-filter must be used at the telescope's entrance to
reduce the energy that reaches the filter. For this purpose, a 200mm x 290mm (8x11inch)
sheet of Baader's renowned AstroSolar Photo Film (Photo ND=3.8) is provided with each K-
Line filter. This material may be easily mounted to any telescope using instructions provided
(see AstroSolar and TurboFilm Mounting ).

The Herschel Safety Wedge Solar Prism may also be used as the energy rejection filter (in
place of the AstroSolar Photo Film). This will provide the absolute highest quality solar
images possible in CaK.

Please note: The Baader K-Line filter is intended ONLY for imaging. It is not suitable for safe
visual observation (the UV levels may pose an eye safety risk from prolonged observations).
Due to the eye's low sensitivity and very poor resolving ability at 395nm, solar features in CaK
are generally invisible for most observers - even through multi-thousand dollar sub-angstrom
dedicated CaK etalons and telescopes. All of these instruments are intended primarily for
imaging.

In addition to imaging the sun in CaK, the Baader K-Line filter opens up another exciting
possibility - imaging of Venus! The narrow bandpass @ 395nm enables imagers to record
cloud structures, with results similar to the dedicated Baader Venus Filter.

Please note - A blue sensitive imager is required. Most webcams will not be suitable.

Price - £205.00

The Astronomy Shop

1 Tone Hill. Wellington

Somerset TA21 0AU

United Kingdom

Telephone: +44 (0)1823 665510