102. Sanger Shepherd's three-colour demonstration outfits, c. 1902
From 1899 E. Sanger Shepherd introduced the three-colour process to the amateur market, so that photographers for the first time could attempt their own colour photographs (see his stereoscopic colour camera, Item 147). These two demonstration packs show the three coloured positives as separate glazed lantern slides (suitable for demonstrating by projection, in the manner of Clerk Maxwell), and in fully exploded form, the blue image on glass and the red and yellow on film C the films have to be sandwiched in precise register between the blue image and a cover glass to form the finished full-colour transparency.
Standard glass lantern slide size 33 x 33 inches (82 x 82 mm) with wide edge binding.