Review Canon RF 50mm f/1.2L USM
The Canon RF 50mm f/1.2L USM is, together with the new RF 28-70 mm f/2L USM, the big news in the area of lenses for the new mirrorless Canon EOS R. The ultra-bright standard lens makes clear what high expectations Canon has for the new system.
AN EYE FOR THE DARK: Canon RF 50mm f/1.2L USM
The Canon RF 50 mm f/1.2L USM is particularly bright. The brightest 50mm from Canon ever, however, it is not. For the range finder system, Canon once had a f/0.95, and in the EOS system, there was a 50 mm f/1.0. The new Canon RF 50 mm f/1.2L USM should be the first super-bright standard lens with excellent sharpness at full aperture. These high performances are made possible in part by the short distance from the mount to the sensor. This allows light rays to reach the sensor more easily and makes other lens designs possible. Those who would like to get into Canon's mirrorless system because of the low weight and the compact dimensions will have to give this 50mm a pass. It namely weighs no less than 950 grams. For a lot of light to pass through, you need a lot of glass.
The Canon RF 50mm f/1.2L USM isn't a little guy, with a length of 108mm and a diameter of nearly 99mm. The weight is 950 grams, and the filter size is 77mm. This makes it a lot bigger than, for example, the Canon EF 50mm f/1.2L USM. The lens contains 15 lens elements, divided into 9 groups. Three lens elements are aspherical, and one is made of glass with a special refractive index. The aperture consists of 10 blades for an extra-round opening. That means that the aperture gives you closed solar stars with 10 points. The shortest setting distance is 40cm. A special feature of the RF lenses is the extra ring at the front. That ring, with a fine diamond-shaped rib pattern, is programmable. You can use it, for example, to set the aperture or for exposure compensation. The ring rotates with small clicks that cannot be turned off. The latter is the only thing that is unfortunate, but otherwise it is an innovation that should be on every lens from now on. The focusing ring is wider and has a pattern of fine lengthwise grooves. Behind that, we find two switches. The top is to switch between autofocus and manual focus, and the bottom one is to limit the focus range from infinity to 80cm, if you're sure you do not need the near range. As an L-lens, it is of course weather-resistant and has an extra gasket at the rear.
The Canon RF 50 mm f/1.2L USM has an annular USM motor. And from a recent 'tear-down' by LensRentals, it appears that it is not just any USM engine. The Canon RF 50 mm f/1.2L USM has the same USM engine as the latest Canon EF 400 mm f/2.8L IS USM. There is a reason for that. The 50mm contains a lot of glass, and to move that quickly, you need a sturdy motor. This approach works. In combination with the EOS R, the Canon RF 50mm f/1.2L USM focuses quickly, also for video. Whereas with previous bright lenses from Canon, such as the EF 85 mm f/1.2L, the lens glides into the sharp point, the RF 50 mm f/1.2L shoots to its focus point as soon as you press the shutter button halfway. The USM motor of the RF 50 mm f/1.2L USM makes a bit more noise than the Nano-USM motor of the RF 24-105 mm f/4L IS USM that we have tested before. As a photographer, you will probably never notice that, but if you film in very quiet spaces, you might hear it.