Using this X - Rite 301 Transmission Densitometer is easy. First, make sure it's connected to a power source using the included power cord. Then, place your black and white x - ray film in the appropriate position for measurement. Depending on your needs, you can choose different apertures for different measurement ranges. When not in use, keep it in a dry and clean place to avoid dust and dirt buildup. If you see any major scratches or scuffs that might affect its performance, it's a good idea to get it checked. Also, be gentle when handling it to prevent further damage.