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.

BUILD 

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.

autofocus

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.

VIGNETTING, FLARE 

The Canon RF 50 mm f/1.2L USM is a particularly bright lens. And bright lenses generally suffer from a lot of vignetting. The RF 50 mm f/1.2L USM is no exception. In RAW, it is almost 4 stops at full aperture, and corrected in jpeg, still 2.5 stops. Stopping down reduces the values quickly to about one stop at f/2.8, and then you hardly see it anymore. We have argued before that vignetting is not always a bad thing. Many photographers use vignetting in the photo as a stylistic tool, to emphasize a subject somewhere in the middle of the photo. This is often used in portraits. Depending on your taste and your subject, this vignetting can thus also be an advantage.

Flare is something with which the Canon RF 50mm f/1.2L USM has little trouble. If you really try and you shoot directly into the sun, you can get some flare. In practice, however, you will rarely suffer from it. The coatings perform well. The example below is the worst we could find in a long series of shots.

DISTORTION

The Canon RF 50 mm f/1.2L USM also performs excellently in the area of distortion. In RAW, the distortion is about a quarter of a percent barrel-shaped, and with the corrections in jpeg, it is much less. Where for many lenses these days, the choice is made for optimizing the sharpness and distortion in the camera by correcting it, this lens does not need corrections on this point. And the fewer calculations a file undergoes, the higher the final quality. And you see that.

IMAGE QUALITY

The Canon RF 50mm f/1.2L USM is a lot bigger than the EF 50mm f/1.2L USM. And it is a completely new design. We therefore had high expectations for this lens. And those expectations are more than met. The Canon RF 50 mm f/1.2L USM is sharp at full aperture. And not only in the center, but also at the edges and even in the corners. In the RAW files, we see a slightly lower score in the corners at full aperture, but that has to do with the vignetting that creates a slightly lower contrast and therefore a slightly lower score. In the jpegs, this vignetting has been partially corrected, and the corners also appear to be sharp. The sharpness increases slightly when you stop down and reaches the maximum value at f/2.8. From f/2 to f/8, however, the differences are negligibly small, so you only have to base your choice of a certain aperture on the required depth of field. Chromatic aberrations are virtually absent in this lens. At full aperture, you still see the phenomenon that blurred objects in the foreground get a magenta edge and blurry objects in the background, a green edge. With shiny objects (sun on the water or shiny jewelry), you see this most clearly. However, it is a lot less than with bright EF lenses that we have tested before. It makes the RF 50mm f/1.2L USM really usable as an all-round standard lens.

IMAGE STABILIZATION

The Canon EOS R does not have image stabilization in the body. And the Canon RF 50mm f/1.2L USM unfortunately doesn’t have it either. Of course, with a lens this bright, you will be less likely to have trouble due to slow shutter speeds. But if you want more depth of field in low light, your shutter speeds should be lowered, and image stabilization can be nice. The lack of stabilization is actually the only point of criticism that we can find with this lens, and it is perhaps more of a criticism for the EOS R than for the RF 50 mm f/1.2 L USM. We don’t have a crystal ball and have no idea what Canon still has in store, but if we could choose, we hope for an EOS R body with stabilization, and we would leave this lens as it is.

Bokeh

The bokeh is great. A beautiful blur in the blurry areas, both in the foreground and the background, is of course what you buy this lens for. And the Canon RF 50mm f/1.2L USM completely lives up to the high expectations on this point. The sharpness in the focal plane is already high at full aperture, and, partly because of that, you can see the gradient to blurry very clearly. At full aperture and with the focus at about a meter or less, a nice distance for portraits, you can use this lens to melt the background completely into soft shapes and colors without recognizable contours, hard rings or other problems. This is an ideal lens to use in very busy environments such as trade fairs, conferences and parties. With it, you emphasize your subject easily, and other things disappear into a soft, blurred background.

ConclusiON Review Canon RF 50mm f/1.2L USM @ Canon EOS R

PROS

• High brightness
• Good image quality right from full aperture
• Beautiful bokeh
• Fast autofocus
• Weather resistant
• Programmable ring

CONS

• No image stabilization
• Significant vignetting at full aperture
• Hefty price and dimensions for a 50mm