I'd like to make a lightning detector for use with my DSLR camera. It should detect when a lightning strike occurs and trigger the camera to take a picture. I know there are some existing schematics for these online, but it'll be more fun to make my own. Below is a first draft of the schematic - there aren't even any part numbers or component values yet. One thing that's likely to change is the phototransistor will probably need it's own higher-voltage biasing.