Get close enough to this raven and you’ll set off the PIR sensor, which triggers lighting and sound effects, including some spooky glowing and blinking red eyes, general cawing, and of course ...

this DIY motion trigger for a DSLR is a quick and easy build, and probably loads more fun. The BOM on [Jeremy S Cook]’s build is extremely short – just a PIR sensor and an optoisolator ...

(Passive InfraRed sensor) A device used to detect motion by receiving infrared radiation. When a person walks past the sensor, it detects a rapid change of infrared energy and sends a signal.