When should fluorescent magnetic powders be used? The choice is dependent on the surfaces which need to be dusted. Surfaces such as plastic bags or shiny magazine covers should be fumed first with Superglue Liquid and then dusted with fluorescent magnetic powders, Similar to Red and Magnetic fluorescent Red powders. Our magnetic fluorescent powder fluoresces strongly when viewed under 450 mm, 485 mm, 525 mm, 530 mm and 570 mm wavelengths of light. It is applied just as any magnetic powder is dusted, using a magnetic applicator. Try using the 570 mm setting on your Forensic Light Source and view the print using red goggles.