William Herschel discovered NGC 4793 = H I-93 = h1475 on 11 Apr 1785 (sweep 396) and noted "cB, pL, about 1.5' south of a [mag 9-10] star." JH made two observations and measured an accurate positon.

400/500mm - 17.5" (5/14/94): fairly bright, moderately large, elongated 2:1 SW-NE, 2.0'x1.0', fairly high irregular surface brightness, broad concentration with no well-defined core. A mag 15 star lies about 1' off the SW edge and 1.7' WSW of center. Located 1.8' S of a mag 9.5 star which detracts from viewing. At 280x, a very small bright nucleus is visible and there is an impression of a dark patch or dust along the NE extension.

Notes by Steve Gottlieb