My Grandfather had an aerial picture of his Michigan tree farm and he had someone transform it into a, roughly 14" X 24" wall hanging picture. However the frame was maybe a couple inches deep and was backlit. He would plug the frame into a wall socket and a light between the picture and the rear of the frame made the pic look as if it were on a slide screen or such. The picture was fairly transparent and was a cool sight to behold. He had it made probably 50 years ago. Where would I start to have a picture done in this manner? I searched the web but wasn't certain exactly what to type into the search window as I don't know what this process is called. I typed in 'backlit pictures' but results were photo tips for - duh - providing backlight in taking pictures. Any advice will be appreciated. Thanks.