Lunt Solar Systems Ca-K Module with 18mm blocking filter in extension tube for 2" focuser (15911)

Calcium K (Ca-K) Telescopes and Filters are specialized instruments used to observe the Sun at the 393.4 nm wavelength. This emission line, produced by calcium, is located just at the edge of the visible spectrum and corresponds to a solar layer that is slightly lower and cooler than the one observed in hydrogen-alpha light. Observing the Ca-K line highlights super granulation cells, which are most prominent in areas with strong magnetic fields such as sunspots and active solar regions. Studying both the Calcium K and Hydrogen-alpha lines provides valuable information about the structure, intensity, and depth of these active regions on the Sun.

The Calcium K line is centered at 393.4 nm, which is just beyond the visible spectrum on the ultraviolet side. While some people can perceive the violet color of this wavelength, many cannot distinguish its contrast due to natural yellowing of the cornea. People who have had cataract surgery often report seeing more detail. For this reason, Ca-K observations are typically carried out with cameras, which can capture detailed and striking solar images.

These filters use internal narrowband technology to achieve a bandpass of less than 2.4 Angstroms, making them primarily suited for imaging rather than visual observation.

Delivered with order:

• Star diagonal with T2 connection, suitable for 2″ focusers

• Blocking filter B1800 with IR and UV protection

Specifications

Capacity:

Connection (to the telescope):
2-inch

Connector (at camera end):
T2

Connection (to eyepiece):
1.25-inch

Half-value width:
2.4

Frame:
2-inch

Appropriate for telescopes:
Less than 102/1620 (Refractors)

General:
Type: Solar filter
Type of build: Line filter