Downtown St. Paul, Minnesota reflected on the Mississippi River. Photographed from Harriet Island.
Photographed well after the sun was down, it was dark enough to make long exposures with little need for any filters. The long exposure helps to intensify the lights reflecting on the water as well as to smooth the surface of the water, removing waves and debris.
When making long exposures it is often convenient to shoot at the lowest possible ISO and maximum aperture (f/22) to achieve the slowest of all possible shutter speeds. However attention needs to be paid to the diffraction effect caused by the narrow aperture setting. Every camera body has a diffraction limit, effected by the aperture setting of the lens, a point at which the image begins to degrade when the aperture is set near the maximum setting. Most camera and lens combinations are optimal at around f/8 to f/11 aperture setting.
The star effect on the lights is created through exploiting aperture diffraction which among other things causes the bright lights to appear as stars. This same scene photographed at f/8 only moments before this shot did not have any stars at all, the lights all appeared to be round (and boring).
ISO 100 – f/16.0 – 120s – 40mm – Tripod – Single Exposure
Canon EOS 5D MkII Body and Canon EF 17-40mm f/4L Lens with circular polarizer.
Photographed in St Paul, Minnesota on 7-18-2014 at 9:30 PM