A fascinating alternative to H-Alpha Solar observation and imaging, Calcium-K occupies the solar spectral line at 3933.7 Å / 393.4 nm. While technically at the extremes of ordinary human vision, this wavelength gives a striking purple and violet hue to solar images and is of particular interest to solar imagers, who find the surface detail revealed in Calcium-K to be distinct from H-Alpha. Calcium-K reveals super granulation cells that are brightest and strongest in areas of high magnetic fields, such as sunspots.
These filter modules are designed to be used with high quality unfiltered Refracting telescopes (they are not recommended for Reflectors), though please pay close attention to the manufacturer's specifications on appropriate modules for specific focal lengths and apertures of telescopes.
The Lunt LS6CaKMDs2 Ca-K is a Calcium-K module in a straight through e...
The Lunt LS12CaKMDd2 Ca-K filter in 90° star diagonal is a Ca-K module...