The Open Cluster M7 (or Ptolemy’s Cluster) is situated in the constellation Scorpius, near the centre of the Milky Way.
This image was taken at IISAC2009, early on the Saturday night before it clouded over. The Milky Way was setting in the West, and I captured 50 minutes of data on this object before it set behind the mountain.
Click the image to download the 1200px wide less compressed version.
This image is my first real deep space (prime focus) image in some time (since January this year!!), so while it’s not in the league of Louie’s beautiful version of M7 that appeared on APOD last week (congrats Louie!), I’m reasonably happy with the image given the lack of data, no flats calibration and the guiding problems I was having at IISAC2009. It really needs to be much deeper and longer to get the golden star field of the Milky Way.
The image was captured with my normal Deep Space Imaging equipment – the unmodded Canon 350D with the ED80, riding on the EQ6 and guided with an 80mm refractor using my DMK21AU04 and PHD guiding.
Exposures were 5 minutes each, with dark frame subtraction in camera. 10 exposures @ ISO800, FL ~ 480mm, F/6.
Thanks for looking.