I do not have extension tubes. The Canon extenders will not work with the EF-S lens which is why I have the Kenko 2x extender. The bumblebee was two cheap third party extenders stacked and wide open at F/16. I often use EF100-400mm f/4.5-5.6L IS II USM +2x III which autofocuses well on EOS R5. Sometimes I use 1.6x crop mode with the 2x extender Buy Sigma TC-2001 2x Teleconverter for Canon EF featuring Canon EF Teleconverter, 2x Magnification Factor, Communication between Lens & Camera, AF Operates at up to f/8, Two Special Low Dispersion Elements, Dust and Splashproof, Compatible with Select Sigma Lenses, Includes Soft Carrying Case. Review Sigma TC-2001 Fotodiox Pro Autofocus 2x Teleconverter - AF Doubler x2.0 for Canon EOS EF Lenses and EF / EFs Cameras (Fits Full Frame) Lens Mount Adapter. SKU: 2x-EF-P. UPC: 847372029525. Quantity. $99.95. VILTROX Auto Focus 2X Teleconverter Extender Converter for Canon EF Mount Super Telephoto Lens 135mm f/2L,200mm,300mm,400mm,600mm,70-200mm,100-400mm and DSLR Camera 5DII 80D 760D 7D,Black. 79. $11500. FREE delivery Mon, Jan 8. Or fastest delivery Fri, Jan 5. These accessories make it easy to expand the versatility of the attached lens. TELE CONVERTER 1.4x increases the focal length by a factor of 1.4x, while TELE CONVERTER 2.0x doubles the focal length. Focal length: 840mm (600mm+1.4x tele converter) Exposure: F/9 1/400 sec ISO1600. Anybody tried out the Canon EF 2x III Extender with the EF 70-200mm f/2.8L IS II USM? I have a Canon 5d Mark III w/ 24-105mm and 70-200mm lenses on the way, I'm wondering how well the extender works with them, especially the 70-200. I'm hoping that it'd work pretty well for airshows and wildlife. The Canon 1.4x lens extender extends the focal length of a lens by 40%, making (for example) a 200mm lens function as a 280mm lens. making them fully compatible with full-frame, APS-H and APS Great colours, good AF. In summary, Kenko extender is very universal to use, Canon extender with L lenses gives better result. PicNoir's gear list: Canon EOS 6D Canon EF 100mm f/2.8 Macro USM Tamron SP AF 17-35mm F/2.8-4 Di LD Aspherical (IF) Canon EF 24-105mm f/4L IS USM Canon EF 70-200mm F4L IS USM +1 more. The 2.0x HD DGX improves upon its 1.4x counterpart by offering full autofocus operation for lenses with a maximum aperture of f/2.8 or brighter, with the same exception for Canon’s 50mm f/1.8 Altura Photo 58MM Tulip Flower Lens Hood for Canon EOS 77D 80D 90D Rebel T8i T7 T7i T6i T6s T6 SL2 SL3 DSLR Cameras with Canon EF-S 18-55mm f/3.5-5.6 is Lens and Select Nikon Lenses $11.99 $ 11 . 99 Get it as soon as Monday, Jan 8 NAZGC.