William Herschel discovered NGC 5792 = H II-683 on 11 Apr 1787 (sweep 727) and recorded "pB, pL, R, mbM, sf a considerable star; the nebulosity joining to it with a little nebulosity towards the following side." His position is accurate. Not observed by JH, but d'Arrest made two observations and seen twice at Birr Castle.

200/250mm - 8" (6/30/84): faint, elongated 5:2 ~E-W, very diffuse, even surface brightness. A mag 10 star is attached at the WNW side of the core 1.1' from center and interferes with viewing.

400/500mm - 17.5" (6/12/99): moderately bright, fairly large, broad concentration with a quasi-stellar nucleus at moments with direct vision. A mag 10 star close WNW of the core detracts from viewing. Initially appeared ~2.5'x1.5', but with averted vision, very low surface brightness extensions oriented E-W increase the dimensions to at least 4'x1.5'. The ends of the arms fade into the background so it was difficult to judge the size.

900/1200mm - 48" (5/16/12): very bright, very large, very elongated over 4:1 E-W, ~6.2'x1.5'. Dominated by a large, bright central region that increases to an intensely bright core. The central region has a patchy, dusty appearance in the outer portion. A mag 9.6 star is attached at the NW edge of the core. A single, thin spiral arm is attached near this star (slightly east) and shoots west for ~2.5', curving very little. There is no counterpart on the east side, but just a very large, elongated, low surface brightness halo that extends east for ~2' towards a mag 14 star.

Notes by Steve Gottlieb