SLRs and mirrorless cameras take interchangeable lenses, but the fitting, or ‘lens mount’, varies from one brand to another, so can’t usually use one brand of lenses on another brand of camera. Independent third-party lens makers offer their lenses in two, three or more different lens mounts to fit different camera brands, but lenses made […]
EF/EF-S mount (Canon)
The lens mount used by Canon DSLRs. EF lenses are designed for Canon's full frame DSLRs but also fit its smaller APS-C format cameras. EF-S lenses are designed solely for these APS-C format DSLRs and can't be used on full frame models.