William Herschel discovered NGC 4393 = H III-361 = h1246 on 11 Apr 1785 (sweep 396) and noted "vF, vL." Caroline's reduced position is on the west edge of the galaxy. John Herschel called it "F; irreg fig; has a line of bright stars preceding."

Harold Corwin notes that IC 3329, found by Max Wolf on a Heidelberg plate, is an HII knot in NGC 4393. IC 3323 is a nearby star.

400/500mm - 18" (5/30/03): faint, large, diffuse glow, approximately 2.5'x2.0' in diameter, extended N-S, very low surface brightness with just a broad, weak concentration. A neat string of 6 mag 11-12.5 stars running NNW-SSE passes 6'-7' W. Located 19' NNW of mag 4.9 14 Comae Berenices. NGC 4408 lies 19' NNE.

Notes by Steve Gottlieb