I have a crazy idea about proposing marriage to your girlfriend. Choose the right time and invite her on a photo session to a park or some other beautiful place. Have a walk and take several pictures of her. Then, at some point of your walk stealthily put the ring inside your camera just where the film is supposed to be. Then ask your loved one to make some shoots of you in her turn. The camera would certainly turn out to be not working, and your girl will inform you about it. Tell her to check the film holder because the problem may be there. And when she opens it, the ring will fall down into her palm. That will be very romantic and your girl won't be able to say no.