Heinrich d'Arrest discovered NGC 753 on 16 Sep 1865 with the 11-inch refractor at Copenhagen. He noted a mag 13-4 star follows by 17 seconds and measured an accurate position (2 nights).
200/250mm - 8" (9/25/81): faint, small, round.
300/350mm - 13" (8/8/86): fairly faint, fairly small, round, small bright core.
400/500mm - 17.5" (11/14/87): fairly bright, moderately large, oval NW-SE, broad concentration. Bright member of AGC 262.
Notes by Steve Gottlieb