10-9-08 - A PST CaK joins my solar imaging setup

Just bought this used PST CaK from Ben Ritchie. It is a replacement unit for his first PST CaK which was very astigmatic and had to be returned. This one has perfect focus judging by the images Ben has posted on the CN Solar forum and on his own website. I was hoping to be able to give a first light report on its imaging potential today, but the cloud never parted long enough to set everything up.

The CaK scopes allow imaging of a layer of the chromosphere which is cooler and lower than the view via a Ha filter. The Calcium K wavelength is at 393.4 nanometres and allows views of super granulation cells. Emerging flux regions can sometimes be seen forming in this layer before they become visible in Ha light and active region detail can persist in the Calcium view long after detail has been lost in Ha.