Brooms and Razors
The following images are of the western portion of the Veil Nebula (NGC6960), also known as the Witch’s Broom, and were taken this last Friday and Saturday night. No flats were used, as the CCD or the filter fogged over before I had a chance to take them on Friday night, and operator error resulted in useless flats on Saturday night.
These are the first images taken using a Razorback Outback Cooler with the DSI Pro II. The Razorback works seems to work well, but fogging is a potential issue as the DSI Pro II was not designed to be cooled. To address this issue I’ve set up a system based on the design by Chuck Domaracki (see Air Dryer for the DSI). I still have some issues to work out, mostly due to the air intake plugging up with ice, hence the lack of flats.
The picture above is composed of sixteen 10 minute subs taken through a H-alpha filter.
The picture above is composed with the H-alpha image above and an OIII image made up of five 10 minute subs. The OIII image needs more subs in order to bring the noise level down. Given that the sky last night was filled with lots of thin high clouds, I’m amazed that OIII images contained useful data.
Astronomy Picture of the Day has an excellent image of this nebula.
October 13th, 2007 at 8:21 am
Nice image of NGC 6960! How did the air dryer work out?
CD
October 13th, 2007 at 7:28 pm
It has worked out very well. The CCD has only fogged over once since I started using the air dryer—it was due to the fact that the inlet tubing filled with ice, blocking the air flow. I’ve since reworked my air dryer and eliminated that particular problem.