How do we paint a Joshua Tree with light? And how do we photograph streaks of light from a passing truck? Let’s see.
This picture has three components that I will discuss. Let’s take a look at the truck’s light streaks first.
Streaks of light
Photographing streaks of light from passing vehicles is quite easy. Basically, keep the camera shutter open and let the truck pass!
Of course, part of it is also timing. This photo was taken along Joshua Tree Highway in the Mojave Desert. There wasn’t much traffic that night. So I waited until I saw a truck coming and then opened the camera shutter. My camera settings on this moonlit night were two minutes f/8 ISO 200. But of course just about any setting can capture streaks from a passing vehicle, as long as you don’t have too bright a setting. Simply determine a good ambient light setting that is long enough for the light streaks to be as long as you want.
Light painting of the Joshua Tree
Painting the Joshua Tree lightly to make it look realistic requires some thought. Or at least solid instinct.
In this case, I wanted the light painting to look relatively natural. Because the truck went up the hill from right to left, light painting of the Joshua Tree from camera to the right seems logical. That’s where the moon shone from.
I was on the right side of the tree. I used an angle approaching the moon and “painted” a low light on the tree with my ProtoMachines LED2, using a warm white light, and did this for several seconds. Then I stepped back and let the truck illuminate it some more, then let the moon bake.
If I had lit the tree from the left, it would look unnatural because the other light sources were coming from the right. This is one of many considerations to keep in mind when painting light.
To create a greater sense of movement in the photo, I’ve also created some star trails. Since I had already determined the correct exposure time for ambient light, I just let the camera click through through my intervalometer. I shot four photos in a row, all with the same setting. In Photoshop CC I just stacked them on top of each other and switched the layer setting from “Normal” to “Lighten” to let the cumulative light shine through, and everything was done. If you want to learn more about creating star trails in Photoshop, read this article.
Above: An intervalometer set to a two minute exposure. It is set to fire 10 shots in a row before automatically stopping. The intervals between photos are set to 1 second, the shortest possible to avoid gaps in the star trails. If you want to learn more about using an intervalometer, you can find an overview in this article.