A professional-quality hidden camera detector is both easier to use and more effective. You can get one for around £100. Professional detectors offer two methods of finding a camera: either they look for that glint from the lens (much like using a flashlight or smartphone), or they detect RF broadcasts from a wireless camera. Some detectors rely on one technology or the other (the cheapest detectors pick up RF), while pricier models include both, a combination of features that's effective at finding different kinds of cameras.
To make visually finding a hidden camera easier, detectors use multiple flashing LED lights or in more expensive models, lasers to help light up camera lenses. They're as simple to use as a flashlight. Simply hold them up to your eye (make sure the lights are facing away from your eye) and activate them while looking around the room. Just like a flashlight or smartphone, you'll have to hit the camera from the right angle to tell it's there, so you'll want to take a slow, careful look around the room, focusing on specific areas where a camera might be hidden. A camera lens should light up in the detector's viewfinder, making it easy to spot