What is an EF-S Lens?
EF-S lenses or “electofocus-shortback focus” lenses are lenses made by Canon for its DLSR (digital single lens reflex) camera range. It is a variation to their existing EF lens range and basically produces the same result when it comes to images it is able to produce. EFS or EF-S lenses are said to be compatible with pre-2003 camera bodies manufactured by Canon. This means that this lens, which was released in 2003, can be mounted on Canon cameras that were released in the previous years.
The ‘S’ or ‘shortback focus’ feature of EF-S lenses refers to the lens’ placement in the camera body. Since this particular lens can be placed deeper into a camera body, the space between the sensor and the lens itself is shorter when compared with standard EF lenses. This lens configuration is said to be helpful in taking very wide-angle shots. But for some people, images taken on standard EF lenses and newer EF-S lenses are basically the same. Another important note about EF-S lenses is the practical side of its deeper placement on the camera’s body. This configuration is said to be cheaper or more cost-effective for Canon which made this lenses for the mid-range DSLR camera market. Because of the lens setup, it is made smaller and lighter which is why in terms of cost, EF-S lenses are less expensive.
With basically the same image quality as that of the standard EF lenses, the only main negative issue for EF-S lenses is that it is compatible only with APS-C sized camera sensors that are released after 2003. This range includes the Canon EOS DLSR range which has the distinctive red and white dots on the lens mount. These dots indicate that they are compatible with EF-S lenses. For the budget-conscious individual, an EF-S lens is still a good purchase. But for those who may change camera bodies in the future, standard EF lenses are recommended as these are compatible with more Canon camera bodies including the EOS series.