If you need to screen print a detailed or delicate design, the photo emulsion method is going to give you the best results. This method requires light exposure, just like film, as the name suggests, but it doesn't have to require any special lighting set-up (unless you want to get fancy)-- you can simply use a dim room, and the help of the sun! The Diazo Speedball Photo Emulsion Kit comes with with both the emulsion and the sensitizer that develops it. A simple two-step process will provide you with a large batch of activated emulsion, which can be stored in a refrigerator for up to 4 months after it's been mixed. Detailed step-by-step instructions are included. This is the most versatile method of screen printing.