There are three different types of lenses for Canon consumer interchangeable lens cameras, these include EF, EF-S and EF-M. When it comes to choosing your lens, you need to ensure that you are selecting a lens that will work with your camera.
The easiest way to find out which lenses your camera will accept is to look at the indicators on lens mount on the front of your camera.
Simply remove the lens from your camera by pressing the lens release button and twisting the lens anti-clockwise.
If you see a red circle on the lens mount your camera will accept EF lenses.
If you see a red circle and a white square it will accept EF-S lenses as well.
If you see a white circle it will accept only EF-M lenses.
The original EOS camera system was introduced in 1987. At its heart was the EF lens mount, connecting lenses to the camera body in a fully electronic way for the first time. Apart from the physical connection between these two components all communication is electronic, allowing for highly accurate, real-time data transfer. Canon became the first to build the motor that drives the focus inside each lens, rather than using a motor inside the camera body. Even with continued development and evolution of focusing systems, Image Stabilizer technologies, specialist lens elements and weather sealing, the original EF mount design remains unchanged. All EF lenses are compatible with every EOS camera ever produced, including the new EOS M series when used with the EF to EOS M Mount adapter.
EF–S lenses are specifically designed for EOS DSLR models with a more compact sized sensor – delivering lenses that are lightweight, versatile and supremely portable. With the EF–S range, Canon’s engineers took advantage of the APS–C sensor size to produce lenses that are not only lighter and smaller, but also offer photographers far greater wide-angle choice. Owners of EF–S mount cameras have access to a complete offering of lightweight lenses extending from 16mm to 400mm (35mm equivalent).
EF-M mount lenses were introduced with the original EOS M range of cameras in 2012. Even more compact compared to the EF and EF-S range they are designed exclusively for use with EOS M cameras. Offering a range from ultra-wide to telephoto to macro they’re portable enough to take everywhere, they’re a great choice for those taking a more creative approach to everyday photography.