I read this post of 7 years ago:DLSR Hotshoe wiring to Arduino
I built the exact circuit described in the answer, shown below, to detect when my canon DLSR hotshoe would send a "trigger" order to the flash. This trigger signal could then be dealt with by an Arduino.
This is the hotshoe of the Canon camera below:
My Arduino detects when I fire the flash (pull trigger to GND,) but the weird thing is that it also detects when I half-press the shooting button, and sometimes keeps detecting if I keep the button half pressed for some time.
When I do shoot it always detects normally, so it works, but something is false triggering when I half press the button - and it's random.
If the camera is on and I don't press the shooting button, it works normally as it should, never detects any false "triggering".
What could I do to fix it? Is the Canon hotshoe trigger different from others?