Quantity   Component name
1 × Raspberry Pi The smaller - low power the better.
1 × Raspberry Pi perma proto HAT ( for prototype )
1 × 4400 mAh USB power supply Enough power for a headless pi for most of a night.
1 × 5 momentary contact pushbuttons Up, down, yes, no and whammy!!! - let's take some photos of galaxies!!!!
1 × 4n36 opto coupler Keeps Raspberry PI power, and the camera's electronics separate. Just so my buddies won't freak with their expensive cameras.
1 × 2.5mm stereo plug and cable Canon Cameras have a 2.5mm port for remote controlling the camera's shutter
1 × 3.5 mm stereo jack To get sound out, when used with a Pi Zero !
1 × Battery powered speaker - amp combo Simple way to make the sound loud. Better to build and audio amp and speaker on the final board.
1 × A Nice Box Mounted on a plate with a 1/4" hole, so the camera can thread over top of the plate and keep the assembly tidy.