If you want the portrayed person’s voluntary collaboration, the best technology for taking paranormal photos is Daguerreotype. Ghosts and other paranormal beings (vampires, gnomes, elves, zombies…) are not very supportive of new technologies. They prefer the classic ‘camera obscura’ with extensive use of chemistry to treat the glass-protected plates as well as long exposures which can last up to several years in conditions of total darkness (paranormal beings avoid the light). The best ghost portraits were obtained using this procedure by Scottish photographer Roger Pickman, who in the mid-19th century, toured the Scottish castles offering ghosts the possibility of having a full-length portrait or just the bust. “Ghost with his head under his arm holding a Dundee cake” is his best-known portrait. But it’s also worth highlighting other artistic variations on the same theme, such as “Ghost with Dundee cake on the head”, “Ghost with Dundee cake under his arm”, “Ghost with head on Dundee cake” and “Dundee cake with ghost head under his arm”. This last photo served as an advertising claim for a famous brand of Dundee cakes until well into the 20th century.