People keep asking how to find hidden cameras. All the questions about this or that detector on Amazon, or using this or that device, when the reality is that your cellphone can see and show you these cameras. I've attached a quick video of the baby monitor camera in my daughter's room. While this is not a good example of a 'hidden' camera since it is in rather plain sight, it still perfectly illustrates the point. When the lights in the room go out, the camera switches on the ring of IR lights around the lense. People can't see this light, it is outside the visible spectrum, but the camera CAN see this light and uses it for low light recording.

Any hidden camera placed in a room is going to have some sort of IR output or the image will be worthless in low light. You won't see it, but your camera will.

Please note: there are a few devices you will have in your home that DO emit IR. Some older model stereos will, TV remotes, fan remotes, LED light display remotes just to name a few. Review what your camera shows you and see if there should be any reason why the IR light you catch on the camera has any reason to be there. This will rule out all of your false positives and help you find actual hidden cameras.