Cannabis yellow creates the light, Adding indigo wasn't dark enough so the logwood was added. Both the brazilwood and the buckthorn are true paint pigments created by making what is called a 'lake'. The dyebath is transformed into a thick pigment by adding soda ash and alum. This separates the pigment from the liquid and is then strained to make a dry pigment. Here it is strained, and used as paint before it is dried.