Canon EF-S 24mm F/2.8 STM

The Canon EF-S 24mm F/2.8 STM is a wide-angle prime for Canon's APS-C cameras, and its EF-S mount fits them directly. On the smaller sensor, 24mm gives a moderate wide view rather than a dramatic one. That framing suits street photography, travel, interiors and relaxed groups.

Canon launched this lens in 2014, and it is still in production today. The main trade-off is size against flexibility. You get a lens that barely changes the camera's shape, but every shot is framed at one focal length. For photographers who value carrying a camera everywhere, that is often a fair swap.

At 4.4 oz (125 g) and just 0.9 in (22.8 mm) long, this lens is a true pancake. It barely extends past the camera's mount, so the whole outfit stays easy to carry.

The 2.69 in (68.2 mm) body width keeps the lens discreet on small cameras. The front accepts 52mm screw-in filters, a handy size for adding a polariser or protective glass.

The single 24mm focal length sets your working distance. On APS-C it is wide enough for streets, rooms and groups, yet close to a normal view for walk-around shooting. With no zoom you compose by moving, which many street and travel photographers prefer.

The maximum aperture is a fixed f/2.8. It admits more light than smaller apertures would, which helps indoors, in cafes and in evening street light. That extra light can help keep shutter speeds usable for handheld work, depending on how much light the scene offers.

Do not expect strong background blur. At typical working distances, 24mm at f/2.8 tends to render much of the scene in focus, which suits reportage but limits subject separation. Stopped down, the seven-blade aperture shapes out-of-focus highlights.

Close focus is useful for a wide prime. At 0.5 ft (16 cm) you can photograph food, textures and market stalls from right beside them. Maximum magnification reaches 0.27x, so the image on the sensor is roughly a quarter of the subject's real size. Our optics score for this lens is 77 out of 100.

There is no image stabilisation in this lens. At 24mm, steady hands often carry you through dim rooms. Video shooters may notice shake, though, unless the camera body itself provides stabilisation. A wall or a small tripod steadies the camera when the light drops further.

Weather sealing is absent too, so this is not a lens for rain or dust. There is no fluorine coating on the front glass either. Those omissions matter most if you shoot outdoors in poor conditions. For fair-weather street work, neither gap will slow you down.

The optical layout is simple: six elements in five groups. Canon includes aspherical elements, whose specially shaped surfaces help correct optical faults such as distortion. Distortion can make straight edges appear curved, so that correction matters when you photograph buildings and street corners. Our construction score for this lens is 15 out of 100.