Canon EF 100mm F/2.8 Macro USM vs Canon EF 85mm F/1.4L IS USM — Which Is Better?

The Canon EF 100mm F/2.8 Macro USM is a life-size macro prime, while the Canon EF 85mm F/1.4L IS USM is a fast portrait prime from Canon's L series. Both are full frame EF-mount primes for the Canon EOS system, so either fits directly on EF-mount EOS bodies. The 85mm dates from 2017, the 100mm from 2000.

The 100mm Macro is the lighter lens at 1 lb 5.2 oz (600 g), against 2 lb 1.5 oz (950 g) for the 85mm. The 85mm is shorter at 4.15 in (105.4 mm) versus 4.69 in (119 mm), while its 88.6 mm barrel is wider than the 100mm's 79 mm.

Both accept front filters, but the 100mm takes 58mm threads while the 85mm takes 77mm. Filters already owned in one size will not fit the other lens directly.

The 100mm Macro is the right tool for filling the frame with small subjects. It focuses to 1 ft (31 cm) and reaches 1x magnification, enough to photograph insects, flowers and detail work at life size on the sensor. The 85mm focuses only to 2.8 ft (85 cm) and offers 0.12x, so it cannot substitute for that close-up work.

The 85mm answers with light gathering. Its f/1.4 maximum aperture is wider than the 100mm's f/2.8, supporting dim venues and shallow depth of field for portraits. Both provide autofocus, a manual focusing ring and an automatic diaphragm, so either lens offers autofocus and full manual control.

The 85mm holds every practical feature advantage here. It offers image stabilization rated at 4 stops, weather sealing, and a fluorine coating that makes the front element easier to clean. The 100mm Macro offers none of these, so handheld shooting in poor conditions favours the 85mm.

Neither lens is teleconverter compatible, so extra reach requires native focal length, not a converter.

The 85mm's optical design is the more elaborate of the two, with 14 elements in 10 groups including one aspherical element. The 100mm uses a simpler 12 elements in 8 groups with no aspherical elements.

The 100mm answers with internal focusing, so the barrel does not extend while it focuses. That helps when working close to subjects, where an extending barrel can disturb them or block light.