I have two positive observation of the ring with my 16-inch under very good conditions.

I noted: with 106x clearly a very faint but sure 3'x4' glow around the core; no ring structure direct visible but because of the contrast to the core it seems to be darker around the core itself; glow/ring best defined to the NE; core itself very bright with small E-W elongated bar

sketch: 16", 106x-180x, NELM 6m5+, Seeing IV
NGC2217.jpg