I would like to spend more time on photography but working overtime at the gas plant, saving for retirement in 2010 is keeping me busy. These HDR shots are mostly taken with my Canon 40D hand held. At 6 frames/sec it works. Of course except for moving objects. Frame # 4 is one shot developed in Lightroom in 3 frames for highlights, midtones and shadows. It is one of the nicest. So It can be done with one shot if you shoot in RAW. The others are between 3 and 7 shots. The Vancouver Harber shot late in the evening is a 7 shot one. -3, -2, -1, 0, +1, +2, +3 stops.