Homemade camera trap: Canon 40D + PIR + LDR + ATtiny 85 in Lunch Box

[Oki_]

Jeesib: Hi, thanks, I am glad that my post is helpful for someone. I will answer your questions, but regarding STL - they are not available anywhere, as it was just "first trial" and the fit of counterparts is not ideal. But if you are aware of it and want them anyway, I can upload them somewhere in next few days.

The Arduino will work fine as a logic for camera trap, but I found it to obig overkill in terms of inputs/outputs and of course power consumption. The LDR is just a sensor for determining the amount of ambient light. What is it used for depends on code. Yes, I only want to take night photos (as only wildlife approaches it at night) currently, but with small code modification, I am able to change that behavior. But I am not able to change its behavior in a field with current setup (I need a computer with Arduino IDE and shield for programming ATtiny). I carry pre-programmed day/night/day&night spare chips if I need to change its function in the field.

The reason to connect the 3.3V directly to related PIN on pin sensor is to bypass the linear regulator and to have only single power loss in step-down converter. So In theory, this option is more energy efficient.

Regarding first black picture - you are right, this could be solved with TTL cable that transfers both shutter and focus signal. Unfortunately, I would need to make custom cable to connect Canon camera with Nikon flash and I found this is more expensive than going wireless - with Yongnuo rf603 II wireless triggers, which support cross-brand wireless operation (transfers both shutter and AF signal from Canon device to Nikon device, etc.).

Regarding box, I seek for bigger (and still cheap) option, so I can fit also whole lens inside.