The Vello Manual Extensions Tube Set for Canon EF/EF-S-Mount allows your lens to focus closer than its normal minimum focusing distance. By placing distance between your camera body and lens, the focusing distance is shortened and magnification is increased. Extension tubes enable macro performance for lenses not otherwise able to focus that close, and are also suited for close-up portraiture. The Manual Extension Tube Set for Canon EF/EF-S-mount contains three extension tubes of 7mm, 14mm, and 28mm lengths. They pair up with the required camera and lens adapter mounts, which add an additional 15mm to the actual extension tube lengths. The extension tubes can be used individually or together in seven distinct combinations to create the desired magnification. For closer focusing use the larger extension tube or stack the tubes together. Extension tubes have no optical elements so do not degrade the quality of your lenses.
These tubes are manual tubes and do not communicate electronic functions, such as autofocus or auto exposure control, between your camera body and mounted lens; both manual focusing and manual exposure control must be used. Since Canon EF/EF-S lenses do not feature a built-in aperture ring, exposure can only be controlled by changing the camera's shutter speed, while maintaining the native preset aperture of the lens. With Canon EF/EF-S lenses, this will be the largest f/stop. Due to the screw-in design of the manual extension tubes, the lens may not sit directly upright but will, however, function normally. Do not to over-tighten screw-in tubes to ensure easy removal of each tube. Additionally, when using the extension tubes, you will lose the ability to focus to infinity.