When Canon said they would be releasing two versions of their R mount 85mm f1.2 lenses, it came as a shocker to most people. Why release the same version of a lens with the same aperture value, then the company said one of the lenses would have Defocus Smoothing (DS), and whilst that sounds intriguing, what exactly does it mean?
Well, According to Canon; “Defocus Smoothing is a new vapor-deposited coating that is added to the front and rear surfaces of one or more of the elements in the lens that has the effect of gradually decreasing the transmission factor from the center to the periphery of the lens” which means you get softer Bokeh (Blur) when you shoot with the lens wide open.
To put this to the test, Photographer and YouTube Educator; Manny Ortiz took both lenses and had a shoot out and while the differences are subtle, he came to the finding that the coating on the DS lens reduces the amount of light that hits the sensor by almost two stops and does affect the Bokeh the lens creates.
Watch the video below to find out more;