Canon RF 85mm F/1.2L USM DS

The Canon RF 85mm F/1.2L USM DS is a portrait prime for full-frame RF-mount cameras. Its defining feature is Defocus Smoothing coating, which softens the edges of out-of-focus highlights. It suits photographers who want that background treatment in deliberate studio or location portraits. Canon introduced it in 2019.

The large aperture and DS coating shape the buying choice. You carry a heavy lens, and the coating reduces the light that reaches the sensor. Choose it for its treatment of blurred backgrounds when that matters more than getting the most light from an f/1.2 aperture.

It weighs 2 lb 10.2 oz (1195 g), measures 4.06 in (103.2 mm) across and 4.62 in (117.3 mm) long. That size sits large on any RF body. The bulk is the price of an F/1.2 aperture covering a full-frame sensor. A screw-in filter must match the 82mm front thread.

At 85mm, you can frame a tight portrait while leaving some space between the camera and the person. Moving back includes more of the setting. Closest focus is 2.8 ft (85 cm), measured from the sensor. That is a minimum focusing limit, so use the distance that gives the proportions and framing you want.

At f/1.2, the DS coating reduces brightness by about 1 1/3 stops. The aperture still provides shallow depth of field, but its low-light exposure benefit is reduced. In a dim venue, allow for that loss when choosing shutter speed and ISO. Automatic exposure accounts for it with compatible camera firmware.

The coating is useful when small lights or bright patches appear behind a portrait subject. It softens their outlines within the blur. Place the person well in front of the background to create separation, then check which bright shapes remain in the composition.

At close portrait distances, f/1.2 can leave a thin sharp zone. Focus on the nearer eye and watch for small movements. Stop down when both eyes or several people need to remain clear. The optics specification score is 88 out of 100.

There is no built-in stabilization. A camera with body stabilization can help with still subjects, while a tripod or monopod provides support during longer portrait sessions. Use enough shutter speed for moving people. The features specification score is 52 out of 100.

Weather sealing helps resist dust and moisture during location work. Use cover in persistent rain. Fluorine coatings on the front and rear surfaces help water and oily marks wipe away, which eases cleaning after a day outside.

Inside, the design includes aspherical elements. Aspherical surfaces help correct distortion and spherical aberration, faults that can bend straight lines or soften focus at wide apertures.

Low-dispersion glass and a BR element help reduce chromatic aberration. This fault occurs when colours focus at different points, causing fringes along high-contrast edges. Correcting it is useful for backlit portraits, where bright light can outline dark hair.