My recent interest in the Anthotype, a process that requires a positive light resist to create a positive image, utilizes sunlight's bleaching action on plant pigments. It is considered a fugitive process unless the print is protected from further exposure to light (except when viewing). Examples of William Herschel's Anthotypes from the 1840's are still quite lovely and stable to this day. Clothing, mostly sleep wear, is cut into a single layer and placed upon the coated paper and exposed to sunlight through a building window from between 2-4 weeks in the summer. The emulsion is made from plant pigments such as grass, red rose petals, mulberries, iris petals and pokeberries which are ground with a mortar and pestle and placed into solution. Please go to my blog francisschanberger.wordpress.com to see documentation of my process.