I found an old telescopic auxillary lens (Vivitar 1.8 x) that happens to fit my Kodak lens adapter. I owned from the 1960s when I was using a Kowa camera (an SLR with a fixed lens). Effectively, this telecon gives me 685 mm equivalence on my Kodak. Attached are some trial photos. The focus is soft around the edges and the camera is hard to hand hold at those magnifications but the results came out not too bad.
down Regent Avenue toward downtown (about 10 miles).
Woman at a bus stop (about 2 blocks away)
Fire and Ice (this one was retouched)