It’s important to document settings and setups for recording sessions, in the event something needs to be re-recorded or fixed later. While many things can be documented by simply writing them in a notebook or typing them into a text file on your computer, what do you do when you need to document mic positions? You could draw crude (or not so crude) diagrams and make measurements using a tape measure.
But an easier solution is to break out your digital camera and squeeze off a few shots. The beauty of this is that you can download the photos from your camera into your computer, and save them right along with all the session files, audio files, text notes, and other information.