Raspberry Pi-Based Cable Shutter Release Now with DIY Optocouplers

While a transistor-based cable shutter release does the job, it has one drawback. Grounding the camera to Raspberry Pi can cause the machine or the camera to have a negative ground. This might lead to a higher total voltage difference and could damage either of them. One way to solve this problem is to separate the camera and Raspberry Pi circuits using optocouplers (or opto-isolators).