Sunday 19 September 2021

Ha Full Disk 18th September

Ha-FD-SS-Apollo-Blocker-Colour A quick full disk of a rather quiet sun taken with the Lunt LS50C etalon, Coronado BF15, 2x cemax barlow and a 1.7a blocker by Apollo Lasky. The addition of the blocker clearly increases contrast on the disk, with the effect of the etalons bandpass being reduced by 0.1-0.2a. The filaments had more contrast and were darker, and the surface had a more textured appearance. Certainly something to explore the use of more!