I selected my location as a road bridge crossing the M4 just east of Junction 15 and made four 30 second exposures, which I combined to give two minutes of traffic trails. I like the flashing indicator lights of exiting vehicles superimposed upon their tail lights, whilst the traffic cones also add to the scene. It was necessary to make my exposures whilst the overlooking bridge was free of traffic, since otherwise vibrations imperceptible to me created a lack of sharpness in the image.
F/32, four 30 second exposures, ISO 400
Accepted: Swansea (2013)