The image above was exposed for 3 minutes at f/6.7, ISO 200. The orange color in the sky is from light pollution. The porch area in the foreground was almost completely dark, and was light painted with an LED flashlight.
Color temperature: The blue/orange color combination in this shot was created by setting a custom color temperature of 3400K in the camera. Of course when you’re shooting in RAW format, you can change the color temperature after the fact — but having a preview on the back of the camera that is reasonably close to your intended result usually leads to more informed decisions in the field. Don’t let the camera do the thinking for you.
I saw from the first test exposure that the sky was a nice orange color at 3400K. The LED flashlight I used to light the dark porch area is pretty close to a daylight color balance. Because I use the flashlight for natural looking fill light at night, I often keep a CTO (color temperature orange) gel over the lens to get a color temperature of about 3000K. This gives the fill light a slightly warmer than neutral tone with the camera set at 3400K. Below is an example of how the porch looked with the gelled flashlight:
Lighting angle: Besides the warm tones created by using the CTO gel, another important detail to notice about the all orange outtake version above is that the lighting looks more flat. When I light painted the orange outtake version I moved around, and held the flashlight from a standing position. This created a more diffuse quality to the light that is especially noticeable when comparing the foreground between the two versions of this image.
The successful warm/cool balanced image has a lot more shape and texture because I used a low angle for almost all of the light painting. I held the flashlight 1-2 feet off the ground for about half of the exposure time. This low angle technique illuminates the front edge of the bricks, but leaves the back edge dark, creating harder quality of light with much more dimensionality.
Warm/Cool: The same camera position, exposure, and flashlight were used for both shots. The only differences are that no gel was used in the warm/cool version in order to render a cool colored foreground, and a low angle was used to give the ground more shape and texture.
The next time you’re light painting, try some shots with low angled lighting for more dynamic results. And to read more about creating shape and texture with all kinds of photographic lighting, I highly recommend the book Light: Science and Magic.