Canon Extender EF 1.4x II. Canon Extender EF 2x II . Sample Images top. Sample Images Intro Specs Performance. Compared Usage Recommendations More. Palm, 21 December 2014. Canon 5D Mark III, Canon EF 400mm f/5.6 L, f/5.6 (wide open) at 1/320 handheld at ISO 100, no lens profile used, Athentech Perfectly Clear v2.) Full resolution. Canon Extender II Compatibility Chart as of May 2008. Newer lenses should work, too. enlarge. Specifications top. Intro Specs Performance Compared Usage Recommendations More . Name. Canon calls this the CANON Extender EF 1.4x II. EF means "electronic focus." There is an autofocus motor inside the lenses — but not in this extender. Canon EF85mm f/1.2L II USM; Laowa 100mm f/2.8 Marco CA-Dreamer 2x; Canon EF-Extender (Teleconverter) read our M43 Speed Booster Compatibility Chart. IPT veteran Sandra Calderbank sold her Canon Extender EF 1.4X III (teleconverter) in like-new condition for $249.00, a Canon Extender EF 2X III (teleconverter) in like-new condition for $259.00 and a Canon EF 24-105 f/4L IS USM lens (the original version) in like-new condition for a silly-low $249.00,, all on the first day of listing in early Date last updated: 06/10/2019 Description These lenses can be used with either the Extender EF1.4X III or the EF2X III. Solution Usable lenses: *: Using an Extender with this lens may result in incorrect autofocus. If your camera has an AF microadjustment function, do the AF microadjustment. Lens compatibility chart. Canon EF Extender 1.4x III Canon EF Extender 2x II Sigma 24-105mm f/4 DG OS Art Sigma 50mm f/1.4 DG HSM Tamron SP 15-30mm f/2.8 VC USD A012* The Canon EF 70-300mm DO USM manual says it will not work with the EF 2X II extender. Will it work (particularly the IS) with the newer E F 2X III extender? No, it will most likely not be fully compatible with that lens. Check the compatibility chart. Canon's EF Extenders . Similary to the 1.4x series, there isn't an appreciable difference between the version II and III 2x Extender, at least as sharpness is concerned. Using a 2x Extender gtTpeEF.