William Herschel discovered NGC 4580 = H I-124 = h1369 on 2 Feb 1786 (sweep 521) and noted "pB, cL, R." CH's reduction is 1.4' northwest of UGC 7794.

400/500mm - 17.5" (4/21/90): moderately bright, moderately large, irregular shape though slightly elongated NW-SE, broad concentration with an uneven surface brightness.

Notes by Steve Gottlieb