Hello what do I do to turn the night vision on please? I have 4 cameras all set up & working fine. But at night I’ll get an alert and then can’t see what it is. It might be a burglar with a knife or a squirrel with a nut. Who knows, its too dark?? I understand it can’t light up & see too far off. But if something is right in front of the camera and can’t be seen, I’m thinking something isn’t set up correctly? Or may be wrong.