The first of the wheel shots was 1/6 sec at f2.8 (ISO 800), while the blurred one was 4 sec at f16 (ISO 100). Tripod used in both cases, and in the first shot the wheel wasn't moving (if it was, the 1/6 sec wouldn't be fast enough to freeze the motion).love the last one ! what speed was that taken at? slow shutter speed?