Kasper Feyrer, Rule of thumbs: Double Positive, 2012, antiqued/distressed pine wood frame (beaten with chain, iron oxide stain), cyanotype on watercolour paper, two dead a alkaline batteries, magnets, mirror inset, “new german antique” architectural glass, thumb fingerprints dusted with bi-chromatic fingerprint powder, 15 x 12 in. (38 x 30 cm)