But what's the big deal? It looks vintage. That's what's so awesome about it.
Here are two of my cameras that I've used for TtV photography: a Kodak Instamatic and an Argus Seventy-Five.
What you do:
1. Place the lens of your camera to the viewfinder of another camera.
2. Compose and shoot. That's it!
I'm thinking about doing a series of portraits like this. I think it would be fun. Here are some of my other TtV shots.