This is actually one of the recommended methods if you have no other options. It's not particularly good otherwise because of the limited visibility cone of the

This is actually one of the recommended methods if you have no other options. It's not particularly good otherwise because of the limited visibility cone of the hidden camera reflections. From experience, the flashlight often tends to occlude the reflections you want to see, or the user isn't in the right place to see the reflections (near the flashlight).