Real rain, at an angle, lit from behind and to the right by the sodium lamp at the end of the alley.
The camera cannot see anything tonight. I want to establish that plainly. A dome housing in weather like this is a plastic hemisphere with water sheeting continuously down the front of it, and whatever is arriving at the sensor is a smeared orange field with occasional dark movement in it. If something happened in this alley during this storm, the recording would be worthless and any competent lawyer would say so in about four seconds.
The red diode is lit.
I stood out in it for a long time to paint this one, under the fire escape, with the lamp shielded because the rain was coming in sideways and the paper was going soft. There is a version of me that would like to tell you this was devotion to the work. The truth is I had got interested in a specific problem and I could not leave it, and the problem was this: how do you paint rain in a way that lets the viewer understand it is falling in front of the subject rather than on it?
The answer, which took most of that night, is that the streaks nearest the viewer have to be longer and softer and much less bright than instinct says, and there have to be very few of them. Almost all the rain in this painting is behind the camera. Perhaps a dozen strokes are in front, and they are the ones doing the work.
What I did not expect was how much the water improves the object. Dry, the housing is a dull grey plastic hemisphere and one of the least beautiful things ever bolted to a building. Wet and lit from behind, it is a dark sphere with a rim of pure light along the top and a red heart in it, and it is the most Baroque thing in this entire series of twenty. Caravaggio would have painted it in an afternoon and been pleased.
The building did not intend that. The building intended coverage. What it got, two or three nights a month, is an object of considerable beauty that cannot see a thing.