M39 with 101mm Borg apo refractor at f/4.1 and Canon 20Da camera at ISO800 for stack of 4 x 5 minute exposures. Taken on a very warm night in July 2007. Taken with HEQ5 mount autoguided with ST402.
M39 open cluster in Cygnus. Taken Oct 30, 2010 with 105mm A&M apo refractor at f/5 with Borg .85x flattener/reducer and Canon 5DMkII at ISO 800 for stack of 5 x 10 minute exposures, Median combined. Used Celestron CGEM mount and NexGuider on William Optics 66mm guidescope. All seemed to work well.