M-100 (NGC-4321) is a grand design intermediate Type SAB spiral galaxy in the constellation of Coma Berenices. It is one of the largest and brightest galaxies in the Virgo galaxy cluster and is 55 million light years from Earth and 107,000 light years in diameter. It was discovered by Pierre Mechain in 1781 and entered by Charles Messier in his catalog as number 100. Its spiral form was first observed by Lord Rosse in 1850.
This image, acquired on June 5, 2018, is a I hour 18 minute integration of 6 minute exposures through the Celestron C-11 at f/2, using the HyperStar III imaging system and the Starlight Express SXVR-H694C color CCD camera, operating at -10 degrees below ambient temperature and binned 1 X 1. Guided, captured and combined using Maxim DL5 Pro. Post processed using PhotoShop CS2, Gradient XTerminator, StarShrink, Carboni's Astro Tools and NoiseWare.