Canon EOS 70D Operation Manual - Page 42

Attaching and Detaching a Lens Image Conversion Factor Since the image sensor size is smaller than the 35mm film format, it will look like the lens focal length is increased by approx. 1.6x. Image sensor size (Approx.) (22.5 x 15.0 mm / 0.88 x 0.59 in.) 35mm image size (36 x 24 mm / 1.42 x 0.94 in.) Attaching a Lens Hood A lens hood can block unwanted light and diminish rain, snow, dust etc. adhering to the front of the lens. Before storing the lens in a bag, etc., you can attach the hood in reverse. If the Lens and the Lens Hood Have a Mount Index 1 Align the red dots on the hood and lens edges, then turn the hood as shown by the arrow. 2 Turn the hood as shown in the illustration. Turn the hood clockwise until it attaches securely. If you do not attach the hood properly, it may obstruct the image's periphery, making it look dark. When attaching or detaching the hood, grasp the base of the hood when turning it. Grasping the hood's edges when turning it may deform the hood, resulting in failure to turn. 42