Canon EF 300mm f/4L IS USM EF300mm F4L IS USM Instruction Manual - Page 2

Thank you for purchasing a Canon product. The Canon EF300mm f/4L IS USM lens is a high-performance telephoto zoom lens for EOS cameras, and it is equipped with an Image Stabilizer. • "IS" stands for Image Stabilizer. • "USM" stands for Ultrasonic Motor. Conventions used in this instruction Warning to prevent lens or camera malfunction or damage. Supplementary notes on using the lens and taking pictures. Features 1. The Image Stabilizer gives the equivalent effect of a shutter speed two stops faster*. The lens also has a second image stabilizer mode that is optimized for following shots of moving subjects. 2. UD lens elements for excellent imaging performance. 3. Ultrasonic motor (USM) for quick and quiet autofocusing. 4. Manual focusing is available after the subject comes into focus in autofocus mode (ONE SHOT AF). 5. The lens is compatible with Extender EF1.4X ll and EF2X ll. * Based on [1/focal length] second. Generally, it requires a shutter speed [1/focal length] second or faster to prevent camera shake. ENG-1