Polaroid transfers required a special machine, Polaroid film, dampened water color paper, brayers and a timer. You put a slide in the top of the machine, exposed the polaroid, counted to (I think) 30 seconds, tore the film apart as quickly as you could, placed it on the watercolor paper, pressed it down with the brayers (firmly but not too firmly), waited another (I think) 30 seconds, peeled the film from the paper, and hoped that enough of the emulsion stuck to the paper. When it worked, the results were soft and lovely. When it didn't, it was a hot mess. About 1 in 5 worked, at least for me. This was one of my favorites -- 5 Tuscan Trees. count 'em.