My home-made 'ghost viewer' just like the original!
I found a pic of the original on the 'net, and downloaded the image, remade a 'reverse' side by shifting images around, and printed it on cardstock....I then bought blue and red transparent sheets on ebay, (the kind for 3D), and cut it and pasted....I made 2 and gave 1 to my dentist w/ a copy of the original print of 13 ghosts w/ the special filter coloring, and YES, it works *just like the original*!! you can just see a little blur in the 'ghost remover' side and see the ghost perfectly when you use the 'viewer' bar. Here is a pic of the completed item:
http://pictures.aol.com/ap/myAlbums.do?albumId=47083.1662.1194500801552.1