লিখবনা How to Detect Hidden Camera in Trial Room? In front of the trial room take your mobile and make sure that mobile can make calls........ Then enter into the trail room, take your mobile and make a call..... If u can't make a call......!!!! There is a hidden camera...... This is due to the interference of fiber optic cable during the signal transfer...... HOW TO DETECT A 2-WAY MIRROR? Place the tip of your fingernail against the reflective surface and if there is a GAP between your fingernail and the image of the nail, then it is a GENUINE mirror. However, if your fingernail DIRECTLY TOUCHES the image of your nail, then BEWARE, IT IS A 2-WAY MIRROR! (There may be someone seeing you from the other side). So remember, every time you see a mirror, do the "fingernail test." It doesn't cost you anything. It is simple to do. This is a really good thing to do. The reason there is a gap on a real mirror, is because the silver is on the back of the mirror UNDER the glass. Whereas with a two-way mirror, the silver is on the surface. Keep it in mind! Make sure and check every time you enter in hotel rooms. Share this with your sisters, wife, daughters, friends, colleagues, etc.