1 day ago · Canon EOS R5 Canon EOS R8 Canon EF 100-400mm F4.5-5.6L IS II Canon RF 35mm F1.8 IS STM Macro Canon RF 24-105mm F4L IS USM +7 more Reply Reply with quote Reply to thread Complain Canon calls this the Canon Lens EF 50mm f/1.2 L USM. EF: Electronic Focus. All modern Canon lenses focus with a motor in the lens. L: Expensive as L. No exact technical meaning other than this being Canon's lingo for lenses with extra durability and weather sealing. L lenses work on all cameras including film and full-frame digital. Canon puts It does however employ Canon’s STM focusing which is smoother and quieter for live view and movie shooting, while also costing almost half the price of the EF 24-105mm f4L IS II USM. The EF 24-105mm STM employs 17 elements in 13 groups and a variable focal ratio of f3.5-5.6 with a seven blade aperture system, and offers a four-stop optical The new EF 24-105 II version from 2016 had some Focus problems though: Canon warns of defective focusing in some EF 24-105mm F4L IS II lenses. These lenses have a 10 digit serial number with embedded date code. Only lenses with serial numbers beginning with 48, 49, 50 or 51 have the focus problems. Canon EF-S 24mm f/2.8 STM Lens Review Canon RF 24mm F1.8 Macro IS STM Review Canon RF 24-105mm F4L IS USM Review Canon announced the new EF 24-105mm F4L II IS USM lens (Amazon/Adorama/B&H). Mark Goldstein tested it on Canon EOS 5D Mark IV and found: It is a new professional standard zoom lens for Canon’s full-frame and APS-C DSLRs, much better than the 10-year-old Canon EF 24-105mm f/4L IS USM lens. xWlys.