So I was playing around with my old 50mm lens that goes on my 35mm camera (film!) and i got the idea to put the lens of the film camera against the lens of my new camera. I had expected to see through the viewfinder of the old camera, but I got something else. Instead, I saw the focusing frame that exists on this camera, which makes sense, I just expected to see through that too.
For those of you who aren't familiar, this ring is what you used on old cameras to ensure your photo was in focus. The inside ring is split in half, and if the image isn't perfectly aligned, that's out of focus. Additionally, the outer ring is geometric, and if you are out of focus, the ring is dark and hard to see through. As soon as you come into focus, it gets clear and easy to see through.
Makes you appreciate your auto focus in your point and shoot cameras, eh?