Detailed Instructions: Using a combination of Nikon and Canon Gear we trigger the lighting sequence using the Camera's Hot Shoe. At the Receiver End we are using a Arduino Uno where we read the pulse on one Digital Input pin and use three more Digital Output Pins to trigger the Relays. We used a Seeed Studio Relay Shield bought at Radio Shack for this. The Relays are wired to the Trigger buttons on Yongnuo 2.4 GHz Hot Shoe Radios each set on independent channels. The three Speed lights are fired in sequence from as little as 20 microseconds to 5 seconds apart. We can adjust the interval/frequency between the flashes with a potentiometer mounted to the MakerShield Kit which we wedged between the Uno and the Relay Shield. The value of the Pot is read from one of the Analog Pins and is mapped to the adjust the Frequency.
Because we used two stacked shields on the Arduino and because we like to show off our MakerBot, we needed to design and 3D print our own case.
From here its just a matter of composition, background lighting and Color of each flash. We used colored gels pulled right out of the Lee sample book which was really convenient when factoring the intensity loss of each color. For the Most Part we set the Speed lights on Manual at from 1/2, 1/1 and controlled the rest of background lighting with the ISO, F-Stop and Shutter.
The Rig can be used with all three Speed lights mounted to it or because each flash has it's own receiver we can separate the flashes to get closer to our subjects in the frame.