This is a wide field view of Messier 33, the Triangulum Galaxy. The large area of sky captured in this image shows really how large this galaxy really is, subtending over 70 minutes of arc in the long axis. This is over twice the size of the full moon. Note the small asteroid line to the lower right of the galaxy. I assume this motion occurred over the two hours of exposure.
Canon 60D with a Canon 100-400mm L lens, set at 100mm. 60 x 120 second exposures for a total integration time of 120 minutes. Captured and stacked in Nebulosity, processed in StarTools, and finished in Aperture.
Click on the image for a larger version.