Sigma 45mm F/2.8 DG DN | C

This Sigma Contemporary prime is a compact full-frame lens for everyday photography. The 45mm focal length suits streets, travel, food and relaxed portraits. Sigma makes it in Leica L and Sony E versions, so pick the one that matches your camera.

The main trade-off is speed against portability. Its f/2.8 maximum aperture is modest for a prime, and there is no stabilization. In return, the body stays small and easy to carry all day. Sigma has made this design since 2019, and it remains in production. That balance suits anyone who puts portability ahead of a fast aperture.

The Leica L version weighs 7.6 oz (215 g). The barrel is slim and short at 2.52 in (64 mm) wide and 1.82 in (46.2 mm) long. A screw-in filter must match the 55mm thread, so buy filters in that size. The Sony E version may differ in weight.

At 45mm, this lens frames subjects close to how your eyes see them. Streets, cafes and market stalls keep a natural perspective. It also suits relaxed portraits, where faces keep familiar proportions. Like any prime, it asks you to change framing by moving your feet.

The f/2.8 maximum aperture is the main optical constraint. It gathers less light than faster primes, so dim interiors and evening streets push you toward higher ISO. Subject separation is also gentle at f/2.8, and backgrounds stay more present than they would on a faster lens.

Closest focus is 0.8 ft (24 cm). That lets you photograph food, flowers or shop-window goods from a short distance. The maximum magnification is a separate figure of 0.25x, which records a small subject at a quarter of life size on the sensor.

Stopped down, the lens serves scenes that need depth. A street corner or courtyard reads clearly from foreground to background at middle apertures. Here the modest maximum aperture costs you nothing, since daylight gives plenty of light.

Weather sealing is the standout feature. It helps keep rain and dust away from the lens internals, which suits travel and street days when the weather turns. Since the lens is small, you can keep it mounted and shooting in changeable conditions.

There is no image stabilization. At 45mm, daylight hand-held shooting is straightforward, but dim rooms ask for a firm hold. As a rough guide, keep the shutter at 1/50s or faster for hand-held work. A steady stance or a nearby support helps in those moments.

The feature set is short beyond the sealing. There is no fluorine coating on the front element either, so keep a cleaning cloth handy around water and fingerprints.

The lens uses eight elements in seven groups and includes aspherical elements. Their specially shaped surfaces help correct optical faults such as distortion and spherical aberration. Distortion can bend straight edges, so that correction is relevant when doorframes and building lines fill a street frame.