Terzan 11 Globular Cluster in Sagittarius
The image below is of a faint globular cluster in Sagittarius called Terzan 11. Dark area surrounding cluster is probably caused by obscurring dust which extinguishes light from an area that is rich with Milky Way stars (compare to star field on the left). The globular is listed as magnitude 16.4 so it is a tough object even for large aperature scopes. Tough to guess the classification as it so faint. Location was confirmed with DSS POSS2 image. I should have posted this before but I mis-filed the images and didn’t come across them until this afternoon.
Images were taken at Fox Park in Wyoming on July 15, 2007 at 03:35 am MDT with a Celestron Nexstar 11 telescope, F3.3 focal reducer, and Stellacam II video Camera. Stellacam set at 14/14 gain, medium gamma, and 256 frame integration (8 sec). Registax4 used to dark subtract, flat field correct, align, stack, end brightness enhance 30 frames.
Sky was mostly clear, some high thin clouds, transparency generally quite good despite the high humidity 70%, dew on everything, temperature about 38°F, and no wind.