Thursday 2 April 2015

CaK Proms and AR12305 - 1st April

The proms visible on the sun in CaK light on the 1st of April were no joke, some of the best and brightest I have seen in some time.  Fortunately I was able to get a shot first thing in the morning when the seeing was at it's best.  Using the Skywatcher ED80 scope stopped down to 60mm to give me an f10 setup, together with a barlow to take the focal length up to 1050mm, the proms were really quite bright alongside the limb, and in part spicules can also be seen.  Seems I hit the sweet spot for seeing with this aperture using the homebrew CaK filter and Imaging Source DMk31 camera.