I have an old vintage camera that I gutted and put a raspberry pi into, similar to this project. I want to light an LED housed in the old flash housing when I hold down the button, as well as running raspistill.
The camera has a switch that closes when the old mechanical button is pressed, leading to a circuit I could connect an LED to. I can't modify the switch/LED part of this easily, but I could connect different wires from the Pi.
If I make the pin set to input with pull up or down resistor, it doesn't light up the LED (not enough current), but it triggers the raspistill script. If I change it to output once it senses button press, it shorts through the switch. What is the simplest way I can set this up without modifying the switch/LED part of the circuit?