<Tr> <Td> Camera Obscura, and World of Illusions </Td> <Td> Edinburgh </Td> <Td> Scotland </Td> <Td> Top of Royal Mile, just below Edinburgh Castle . Fine views of the city </Td> <Td> Edinburgh's Camera Obscura </Td> </Tr> <Tr> <Td> Camera Obscura (Greenwich) </Td> <Td> Greenwich </Td> <Td> England </Td> <Td> Royal Observatory, Meridian Courtyard </Td> <Td> http://www.rmg.co.uk/see-do/we-recommend/attractions/camera-obscura/ </Td> </Tr> <Tr> <Td> Camera Obscura and museum "Prehistory of Film" </Td> <Td> Mülheim </Td> <Td> Germany </Td> <Td> Claimed to be the biggest "walk - in" Camera Obscura in the world . Installed in Broich Watertower in 1992 </Td> <Td> http://www.camera-obscura-muelheim.de/cms/the_camera.html </Td> </Tr> <Tr> <Td> Dumfries Museum </Td> <Td> Dumfries </Td> <Td> Scotland </Td> <Td> In Dumfries Castle . Claims to be oldest working example in the world </Td> <Td> Dumfries Museum </Td> </Tr>

The small opening that allows light to pass through the lens of a digital camera is called