Janez Puhar’s Missing Formula (2000)

"Janez Puhar's Lost Formula" explores the life of the Slovenian inventor of glass-plate photography through the eyes of Robin Crichton, a Scotsman puzzled by Puhar's lack of recognition in the West. Crichton journeys to Slovenia to uncover the truth behind the celebrated inventor. Puhar claimed his photographic plate used mercury, sulfur, iodine, and possibly varnish. However, his actual formula has never been documented, as these ingredients are known to be insensitive to light. Crichton investigates whether the four existing Puhar originals are authentic or simply errors by Slovenian historians and museum experts.