400/500mm - 17.5" (11/28/97): HCG 99b is the brightest of a faint and close trio. Appeared faint, very small, round, 0.4' diameter. Contains a very small brighter core with a fainter halo. Forms a very close pair with the "C" component just 0.6' W of center. The "A member (UGC 12897) lies 2.2' SE adjacent to a mag 11.5-12 star.

600/800mm - 24" (11/24/14): fairly faint, fairly small, round, 25" diameter. Contains a small bright core that increases steadily to the center. CGCG 499-033 = HCG 99C is at the west edge of the halo.

24" (10/3/13): the brightest of 5 members in HCG 99 appeared moderately bright, fairly small, round, 30" diameter, increases evenly to a brighter quasi-stellar nucleus. HCG 99C = CGCG 499-33 is attached at the west end with UGC 12897 = HCG 99A 2.3' SW.