One frustration I've had in photography is to get good photographs of a Christmas tree, or Christmas lights on a house, with the exposure set to show the scene nicely but without the lights being overexposed, which makes them blank white.
Here, I found solutions to the problem. The first solution was happenstance: I took a photo of my Christmas tree, but with the window blinds open behind it, showing bright white snow on a neighbor's house. This was around sunrise, but in dim cloudy conditions. The result was the lights were not overexposed. (This image is a crop of the original image. The original was at f/4, 18mm, 1/4 sec, and ISO 100.)
The second image was an attempt to take a photo of my house with a dusting of snow on the roof, with my string of blue Christmas lights. The original had the lights overexposed and completely white. But I took a set of varying exposures, including short exposures showing only the blue lights (the lights the correct blue color, and everything else underexposed to essentially black). I then combined two images, a bright one with the lights overexposed, with an underexposed one showing only blue lights. This is the tricky part. I reworked some Java code I'd written a year or two before, that can open images and modify it pixel-by-pixel. In this case, my new program opened the two images, selected a pixel from the one image or the other to copy to the output image. The selection criteria was brightness of the second image (which showed only the blue lights). I tweaked brightness and saturation on the selected pixels to get the blue lights as realistic as possible.
Here are the two originals. The first is at f/4, 18mm, 1/13 sec, and ISO 100. The second one has identical settings except 1/320 sec exposure. All of these photographs were taken with a Sony \(\alpha\)6000 MIL camera fitted with a Sony G 4/18-105 lens.
The last image is a bit of accidental art, before I got my program to work. I have no recollection what was in my code that produced this. But it is a striking image (note the blue lights).
