The Kenko DG Auto Extension Tube Set for Canon EOS AF Mount is a versatile tool designed to enhance your macro photography experience. These extension tubes allow your lens to focus closer than its standard minimum focusing distance, effectively magnifying your subject. This makes them an invaluable asset for capturing detailed close-ups in macro photography.The set includes three tubes of varying lengths - 12mm, 20mm, and 36mm. These can be used individually or combined to achieve the desired level of magnification. By increasing the distance between your camera's lens and film plane, these tubes enable your lens to focus much closer than usual. Unlike many alternatives, Kenko's Auto Extension Tubes maintain auto focus and TTL auto exposure with most Canon lenses, given there is sufficient light to activate the camera's AF system. This feature ensures that your images retain their original optical quality, making these tubes a cost-effective alternative to investing in a dedicated macro lens.Please note that using these extension tubes will limit your lens's focus range to a very close focusing distance and will not allow it to focus to infinity. Additionally, there may be a light fall off equivalent to 3 f-stops when using multiple extension tubes together. This could affect the camera's ability to auto focus, and manual focusing may be necessary in some cases.The DG Series of Kenko Auto Extension Tubes have been upgraded with "Gated-Array" circuitry for improved performance with digital SLR cameras and some new digital-only lenses. However, they continue to work seamlessly with film SLR cameras and lenses as well. In summary, the Kenko DG Auto Extension Tube Set for Canon EOS AF Mount is a durable, high-quality, and affordable solution for photographers looking to explore the world of macro photography without compromising on image quality.