NGC 4571 is a spiral galaxy located in the constellation of Coma Berenices that William Herschel thought was Messier 91 in Charles Messier' catalog of deep-sky objects, before nearly two centuries later that object was determined to be the nearby barred spiral galaxy NGC 4548.

400/500mm - 17.5" (5/23/87): fairly faint, moderately large, round, 2.5' diameter, diffuse, weak concentration. Located 2.8' SE of mag 8.5 SAO 100177.

900/1200mm - 48" (2/18/12): Malin 1, a giant low surface brightness galaxy, lies 6.8' NNE of the center of NGC 4571. At 287x, it was immediately picked up as an extremely faint, non-stellar glow. At 488x, it was visible ~75% of the time with averted vision as a very small, round, low surface brightness, ~10" diameter. With direct vision, a faint stellar nucleus was occasionally visible.