You don't have to keep your camera up all the time to spot documents and recordings. In fact, when you're looking at recordings you will actually receive a notification in the middle of your screen. This notification, which looks like a camera, is easy to miss during intense moments, so keep an eye out and it will warn you of a nearby recordings that you can capture. You should also pay attention for any enemy movements like flashlight beams, glowing eyes, and other telltale signs that a cultist might be nearby.