Como Bridge is a former railway bridge, now pedestrian path and cycle way. It is really dark at night to say the least only being lit by two small solar lights towards the middle of the bridge. The first shot was taken with a Schneider 40mm lens at f/11. The second shot was taken with an Olympus M.Zuiko 9-18mm lens set to 9mm and f/5.6. In both cases the shots were for 60 seconds, ISO200 and the camera was an Olympus E-P1. The time between these shots is 1 hour. I have used a passing train on the new rail bridge (relatively speaking) to illuminate the bridge but despite the extra exposure in the second shot, it still isn't really enough and noise was impossible to deal with. The difference in the lighting was the loss of reflected light off the clouds overhead which disappeared in that hour. The different hue in the lighting on the bridge is from the railway signals.