This post’s photos were not “manipulated”.
They were single-exposures, taken in available light (no flash) with a hand-held camera, on or near Market Street, San Francisco on the night of 14 October 2012.
We had not stumbled upon the shooting of a scene for a “major motion picture” of the ghostly, supernatural, or steampunk kind.
It was just another normal autumn night in ‘Frisco – if one accepts that any urban-Californian night can ever be normal.
There is a non-supernatural explanation for the “surreal” appearance of some of this city’s central streets, most especially on chilly nights.
For nearly a century, in San Francisco’s CBD, many major buildings (and/or their taps’ water) have been heated by steam.
Beneath the city are two massive boilers which send steam through circa 21 kilometres of underground pipes.
Some of that steam escapes (or is “bled”) through vents and manhole covers on streets and footpaths, most especially on and near Market Street.
Click here for a fuller explanation.