M51, the Whirlpool galaxy and its neighbor NGC 5195 are surrounded by a wide expanse of sky that can appear empty of other galaxies but this inverted version shows they are not alone.
Details
2011-04-22 at the Victoria Centre Observatory.
127mm TV with modified Canon T1i camera on Paramount ME.
Exposure, 7-2 min plus 5-8 min guided exposures with 6-8 min darks and 8-flats for calibration.
Processing in Images Plus and Photoshop.