This photo of the Hercules Cluster (M13) was taken on the night of 13-Aug-2007. It is a composite of six one minute exposures at ISO 800, taken with a Canon Digital Rebel XT, through an 8 inch f/5 newtonian reflector. The exposures were autoguided with PHD Guiding software from Stark Labs, using a Meade DSI color CCD camera on the piggy-backed guide scope, an 80mm f/11 refractor.

The six one minute exposures were processed and combined using Iris software from Christian Buil.

Compare this photo of M13 with the two earlier photos seen in this gallery, which were made with the same camera and under similar conditions - the difference is in the guiding and image processing software - and the remarkabe fact is that the authors of these applications, Craig Stark and Christian Buil, make them available to the public at no charge!