I love shooting in science labs. I enjoy learning what the scientists and engineers are working on and creating that will impact our lives in the years ahead.
Here I used two color gels to help communicate "science." I used blue on the background and red on the foreground.
To get a gel to be the same color it is in the shot it needs to be 2-stops darker than the main light on the subject. So here the main is f/11 and the background blue is metering at f/5.6. The same for the foreground red at f/5.6.
You will notice the power for the blue is full power. The reason for this is the blue gel absorbs more of the light than red does.
The main light is a 30º grid on a monobloc. This is the keep the light from spilling over onto the red or blue and watering down the light.
View the test images on the back of digital camera and make adjustments when needed.