William Herschel discovered NGC 4593 = H II-183 = h1375 on 24 Apr 1784 (sweep 205) and recorded "pB, cL, E, mbM but the brightness confined to a small place." JH made two observations and first logged (sweep 147) "vsbM, to a * 11-12m, with a faint chevelure."

400/500mm - 17.5" (2/28/87): fairly bright, moderately large, elongated WSW-ENE, very bright core, stellar nucleus. First of four within a 32' field including NGC 4602 19' NE. Contains a Sy 1 nucleus and also a Markarian object.

17.5" (1/31/87): moderately bright and large, strong bright core, elongated WSW-ENE.

Notes by Steve Gottlieb