Using digital photo camera on board of RC plane

Good afternoon! I installed a digital camera on R/C model of airplane. All is fine, but there is one minus - pressing the shutter button is using the servo, so it's done mechanically. I would like to alter that part in the e-governance. Already have a board of electronic key, in which the input PPM signal and the output are two wires, which are circuit or non-circuit, it is essentially relay.
I thought that when pressing the shutter release button in the camera is a simple-circuit. When I disassembled it, I saw something a bit more tricky.
I rang and found a couple of contacts that are shorted circuit when you press the button, but if they close the circuit, then the photographing is not happening. How to solve this situation? What is the principle of shutter button? Actually, I need to have two wires from camera, circuiting which leads to the process of photographing.
Thanks in advance for your replies!

Pressing the button is done in two stages.

First you press the button down a little ways. This causes the camera to focus and to check brightness level. It takes about one second.

Then you press the button all the way, to trigger the shutter and take a picture.

So you may need two activating circuits: one to activate the first stage, then another to activate the shutter circuit.

I don't know whether the first circuit needs to be released, or whether it should stay in contact, while you trigger the shutter.

This must be a common hurdle because a number of R/C pilots take pictures/videos from their planes. They like to put up videos on their websites. Try an internet search to see how they solved the shutter activation problem.