Canon EF 70-200mm f/4L IS USM EF70-200mm F4L IS USM Instruction Manual - Page 5

1. Mounting and Detaching the Lens See your camera's instructions for details on mounting and detaching the lens. The lens mount has a rubber ring for enhanced water- and dust-resistance. The rubber ring may cause slight abrasions around the camera's lens mount, but this will not cause any problems. If the rubber ring becomes worn, it is replaceable by a Canon Service Center at cost. • After detaching the lens, place the lens with the rear end up to prevent the lens surface and electrical contacts from getting scratched. • If the contacts get soiled, scratched, or have fingerprints on them, corrosion or faulty connections can result. The camera and lens may not operate properly. • If the contacts get soiled or have fingerprints on them, clean them with a soft cloth. • If you remove the lens, cover it with the dust cap. To attach it properly, align the lens mount index and the K index of the dust cap as shown in the diagram, and turn clockwise. To remove it, reverse the order. ENG-4