YONGNUO Extender EF 2X III (Teleconverter) for Canon EOS

When it works it gets the job done. The loss of sharpness is as expected. Loss of auto-focus is also as expected, depending on the lens and camera combination. For some combinations where auto-focus shouldn't work (e.g. older camera and lens slower than f/4) I had the good surprise to get a somewhat usable auto-focus. The only - but substantial - disappointment is that the extender doesn't work at all with a Canon Rebel T7i and a Sigma 150-600mm Contemporary: I just get an error message telling me that the communication between the lens and the camera failed. In that situation, the EXIF won't have the focal length aperture data. Also, remote focusing from a laptop won't work at all. However, in all fairness, as it is a compatibility issue between Yongnuo, Canon and Sigma, I can't put all the blame on Yongnuo.

At half the price of the Canon extender on which it is based, this is good value. The build quality is good and it mounts very solidly to both the camera and lenses. The colour of the body is a close, but not exact match for Canon's L series lenses.In common with all extenders, you will lose 2 stops of light, so don't expect to be able to use it for sports or wildlife shooting. I'll be using it for landscapes, city capes and moon photography, so fast focus will not be an issue. Autofocus is patchy, depending a lot on having a fast lens and the camera body used, but in my experience this is true of all extenders.Optical quality seems pretty good. There is a slight drop in sharpness and some CA is introduced (see the close-up of the light hood in the 2nd image below.), but this is easily eliminated in post. It doesn't appear to impact colour rendition.These samples were all shot from the same position with a Canon L 100-400mm and an old Vivitar 500mm mirror lens. The first 4 are from the Canon, the first two are without the extender and the second two with. The final four follow the same sequence with the Vivitar. The softness in the final four images is down to the Vivitar rather than the extender.

Me ha encantado el duplicador, funciona muy bien y queda ensamblado a la perfección en. Mi equipo es una Canon 6D y el objetivo un 70-200 f:2.8 L USMSin ninguna duda volvería a comprarlo, me ha parecido un opción fabulosa