The Sun 12-9-08 - First Light for the PST CaK !

Well the weather forecast was supremely optimistic again today with sun symbols all over the place at the Met Office. Up to 9am it was indeed clear and sunny, but the seeing was abysmal so I decided to wait and see if it improved. Of course it just went downhill from there with complete cloud cover till 4.30pm. A brief hole in the cloud between 4.30-5.30pm allowed me to setup the mount and try out the CaK for the first time. Getting the exposure just right is quite tricky in CaK light! I needed more gain than is usual for Ha, but when you get it right the detail just pops out on the screen. Lots of tiny bright plage spots and a much grainier surface than in Ha which resembles the white light views of the granular surface. Not much to see today of course but it will be great fun to image with when the activity levels rise. The quality of the image is superb, no astigmatism whatsoever. I took 1700 frames and had 243 to stack after aligning at a 90% quality threshold.

Also did a Ha disk. Fairly small proms around ths disk and no sign of the spots making up AR1001 which apparently appeared yesterday.