A number of years ago, I built a DIY open air Photo Booth for a friends wedding. I used the "booth" a number of times for various events, but wanted to alter the setup for a simpler configuration. Basically, a dSLR on a tripod, and a laptop for times when I don’t want to lug the big photo booth around. I still wanted a simple way to kick off the photo booth sequence without having to use the laptop keyboard, so I decided to make a Big Red Button. My take on this uses a Teensy LC to send the F4 keyboard stroke to the laptop. Here is how I created the button.

Parts List:
Big Red Button

12’ Micro USB Cable

4.7 “ x 4.7” Project box
Teensy LC USB Development Board

I cut a hole in the project box, 3/4" and had to use a dremel to make the opening a bit wider for the button to fit. I also added felt feet to the bottom so the box wouldn't scratch the surface that is sat on.

I use dSLRRemote Pro from Breeze systems as my photo booth software.

Step 1: Wiring the Button

The Big Red Button is a simple momentary switch with LED. I used a Teensy LC circuit board that will use arduino to program it to be a USB keyboard. I also cut a small hole in the side of the box for the USB cable to enter the enclosure. I then soldered a few jumper cables to the Teensy LC board. 2 of the wires are to power the LED. The Teensy has a 5V output, and the button I got said that it can handle up to 12V, so I didn't bother to use any resistors. I connected the jumper for the momentary switch to the 4th position, simply because the code I used on my last photo booth project also used number 4. You could pick any one you wanted. Once everything was connected properly, I plugged it into my computer to upload the new code.

Step 2: Teensy LC Code

I poached the code off my last Teensy project, and simplified it to work with one button. The dSLR Remote Pro software uses the F4 key to initiate the photo booth sequence. You can change the code to send whatever keystroke that you need. In order to upload this sketch to the Teensy, you will need the following software:

Arduino - Install me First!
Teensyduino

After installation of each of these applications, open Arduino. Under the Tools menu, set the board to Teensy LC, or whatever Teensy board you purchased. Also, under tools, set the USB type to Keyboard. Paste the code I have listed below, and then under the Sketch menu, select verify/compile. Once it completes, it will load the Teensyduino application. Press the button on the Teensy board, and the code will be uploaded and the Teensy will restart. Viola! You now have a 1 button keyboard. Test your button!

Here is the code I used:

/* Photobooth LED Button */

// Setting variables that correspond to the PIN number
const int boothStart = 4; // Red Start Button - 4
int startButtonStatus = 0;

void setup() {
pinMode(boothStart, INPUT);
}

void loop(){
// Check Button Status
startButtonStatus = digitalRead(boothStart);

// If boothStart button is pressed
if (startButtonStatus == HIGH) {
Keyboard.set_key1(KEY_F4);
Keyboard.send_now();
Keyboard.set_modifier(0);
Keyboard.set_key1(0);
Keyboard.send_now();
delay(500);
}
}

Step 3: Photo Booth Testing!

I participated in a local Extra Life event, which is a charitable organization where gamers raise money for Children’s Miracle Network with the motto, Play Games, Heal Kids!. There were a large number of gaming systems, and they had tournaments on some old school games.

I used a large ~60" TV on a rolling cart, with the camera on super clamp with ball head mounted below the TV on the AV cart.. Although completely unnecessary, the Big Red Button button does add a little flare to the open air photo booth. The kids got a kick out of pressing the button! I donated my Photo booth and printer for this event, and let people use the booth for free upon admission. Pictures above show the setup for the open air photo booth, and the Big Red Button in action!