Model Overview. Built with distance in mind, the Canon EF 1.4x II Extender offers extra zoom for that all important moment. As an added extra to the lens, it provides excellent focal range without comprising quality. It offers a perfect lightweight option to mulitiply the focal length without investing in a new lens. I had a 1.4X on my EF 100-400mm and was 100% completely satisfied with the image quality, I never took the extender off that lens. Another bonus buying the 400mm f/2.8 over the 600mm f/4 would also be carrying around a smaller and lighter lens. Rol Lei Nut wrote: Ended up getting the Kenko Teleplus Pro 300 AF DGX 1.4x. On a Sony A7Rii body, MC-11 adapter and Canon 70-200 4.0 IS L, 70-300 L, 100-400 II L & 100 2.8 Macro USM, AF works well (or at least as well as the lenses do without an extender). Not used extensively yet, so plenty of time for any glitches to come out. EF 1.4x III and EF2x III extenders are recommended for use with EOS Digital Cameras. *1: EOS-1D Mark II, EOS-1Ds Mark II, EOS-1D Mark II N, EOS-1D, EOS-1Ds. *2: EOS650, EOS620, EOS750, EOS750 QD, EOS850, EOS850 QD, EOS700, EOS10S/10, EOS REBEL/1000, EOS REBEL S/1000 F, EOS REBEL S QD/1000 FN QD, EOS ELAN/100, EOS630/600, EOS RT, EOS-1, EOS Canon Extender EF 1.4x III. Extends the master lens focal length by 1.4x. Outstanding image quality. Highly resistant to dust and water. £ 479.99. Eligible for free delivery. EF (full-frame) lenses have a red dot, EF-S (APS-C sensor) lenses have a white dot. The EF-S lenses extend further into the camera body so will NOT mount to an EF TC. I have no problems mounting the Sigma 1.4 and 2.0 TCs to my (EF mount) Sigma 70-200 2.8 for use on my 500D but the TCs are useless on my (EF-S) kit lenses and my 60mm macro. I have a 60D and a Canon EF 1.4 Extender II, I was wondering if it would be compatible with the Canon EF 70-300mm f/4.0-5.6 IS USM Lens? As others have said, the short answer is no. You can buy a Kenko 1.4x which will fit, but you probably wouldn't be happy with the results. Canon E-72II Lens Cap. $13.50. $15.00. Buy Canon Extender EF 1.4X III features EF Mount Teleconverter, 1.4x Magnification Factor, Microcomputer Controlled, Communication Between Lens & Camera, Spectra Coating Reduces Ghosting/ Flare, Protective Fluorine Coating, Dust and Water Resistant, C. The 1.4X II tele converter is a update to Canon's earlier 1.4X TC. The mark II allows this extender to be stacked with another of Canon's extenders without having to separate the two with an extension tube. The 1.4X II is a great way to extend the reach of compatible lenses. I have used it with Canon 300mm f4 IS, which turns it into a 420mm. That Kenko 1.4x works well with my 7D II and 100-400 II. Since Dave says it works, you'll be fine. The IQ of the Kenko converter is good, the Canon may be a tick better but that's splitting hairs. One advantage should be the additional focus points. BfBp3N.