In front of the Ashmolean museum they’ve built a camera obscura.
A camera obscura is basically a pin hole camera. This one you can walk into.
For this one the inside was covered in white fabric and the floor and ceiling was painted white. The “pin holes” were about 1.5″ in diameter.
The image generated on the wall was remarkable.
It would be fun to set one of these up at the various festivals in the area. I don’t think I’ve seen one before, but I wouldn’t be surprised if they have had one of these for da Vinci Days in Corvallis.