I believe this is the first time I am posting a high-resolution Calcium-K image of the Sun.
The high-resolution Calcium image on the right shows an ultra-violet lower atmosphere of the sun illuminated by emission of Calcium atoms.
A full disk solar disk Calcium-K image from SDO provides a sense of perspective for the high-resolution Calcium-k image. This image was taken with a 11-inch Celestron Schmidt–Cassegrain solar telescope fitted with a full-aperture Dielectric Energy Rejection Filter which enables it to observe this selected layer of the Sun. A LUNT B1200 CAK module and a Basler ace acA1920 was used at the rear. 2000 frame video recordings were made, from which 1000 frames were stacked to produce a high signal-to-noise ratio image.
With an excellent resolution (image scale of 0.15 arc-second per pixel), the telescope shows detailed features on an area of 88,900km in the solar atmosphere that is 150 million km from Earth!! Right now the Sun's lower atmosphere is quiet with web-like pattern of irregular shapes. Bright areas indicate the presence of strong magnetic field concentration whilst small darker areas are regions with weaker magnetic fields. Interesting intermittent localised small bright points (K-grains) can also be observed. There will be more interesting features in this layer of the Sun when it gets more active in the coming days.
Comments are welcome.
Alfred