Lunt Solar Systems Filters Ca-K module with 18mm blocking filter in star diagonal for 2" focuser (15946)

Calcium K (Ca-K) telescopes and filters are designed for observing the Sun at the 393.4 nm wavelength, which is produced by calcium and sits just at the edge of the visible spectrum. This emission line reveals layers of the Sun that are slightly lower and cooler than those seen in Hydrogen-alpha, highlighting super granulation cells that are most prominent in regions with strong magnetic fields such as sunspots and active solar areas. Studying both the Calcium K and Hydrogen-alpha lines gives astronomers valuable information about the structure, strength, and depth of solar activity.

The Ca-K line is centered at 393.4 nm, which is just outside the visible spectrum on the ultraviolet side. While most people can see the violet color of this wavelength, many cannot perceive the contrast due to natural yellowing of the cornea. People who have had cataract surgery often see more detail at this wavelength. For this reason, Ca-K observations are typically performed with cameras, which can capture fine solar details that are difficult to see visually.

Internal narrowband filters provide a bandpass of less than 2.4 Angstroms, making this system ideal for detailed solar imaging.

Delivered with order:

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

• B600 blocking filter with IR and UV protection

Specifications

Capacity

• Designed for use with solar imaging systems.

Connection (to the telescope)

• 2" barrel, compatible with telescopes that have a 2" focuser.

Half-value width

• 2.4 Angstroms, offering a narrow bandpass for precise solar imaging.

General

• Type: Solar Filter

• Type of build: Line filter (Calcium K narrowband)

This system is best suited for imaging the Sun in the Ca-K line, allowing astronomers to capture features that are otherwise difficult to see visually. Always use the included blocking filter for safety and optimal performance.