[luka]

Sorry, must keep it short.
Regarding the separate Peltier power VT1 controls the GND to the Peltier there are few options. There is no space on the PCB to insert an DC-DC converter so we could:
1. Have the converter "dangling" in the case, hot-glued to the side (more heat inside the case but simpler if we have space).
2. Have the converter outside the case. Outside the case could mean attached to the camera (I could 3D print a small housing) or even completely detached, on the ground (floor), with a custom-made 3-pin power cable going to the camera.
3. Use two separate power supplies with shared ground, one for Peltier and one for the rest of the camera.