The latest Star Wars films have million dollar CGI and special effects budgets but all these guys had was a lamp and a plaid blanket and they made a film that was way better.

I think it’s more akin to a projected picture of a wool blanket, because light shining through a real blanket would be diffuse and not project a crisp image.

If it was a lamp, then the blanket, then a lens to focus the image, then that could work. But at that point why not just shine the light through an image on film before hitting the lens, rather than use an actual blanket.