Saturday, 26 July 2014

CaK Closeup 26th July

A closeup of the activity that is rounding the suns eastern limb at the moment.  Some of these are sunspot corpses of AR12107 and AR12108 very close to the limb; 2 -3 weeks ago these were sat squarely mid disk and were the focus of much attention, but now there activity levels have dropped right off.  My latest variation on a theme with my CaK filter seems to be working very well, with the problem of ghosts and reflections dealt with.  As a result prominences and the double limb feature (normally only seen in Ha light) are easily and repeatably visible.  Out of band blocking is the key in suppressing photospheric light and getting more contrast on the disk.