Sony FE 20mm F/1.8 G SEL20F18G

The Sony FE 20mm F/1.8 G is a wide-angle prime for full-frame Sony E-mount cameras, released in 2020 and still in production. It suits landscape, architecture, interiors, astrophotography and street work, where a broad view and a fast aperture both help.

The main trade-off is the fixed focal length. You frame at 20mm and move yourself to change composition, and there is no zoom for quick flexibility. At 13.2 oz (373 g), the lens stays light enough to carry all day, which suits travel and long walks after dark. It also works well as a second lens beside a standard zoom.

This is a compact wide prime. The barrel measures 2.89 in (73.5 mm) across and 3.33 in (84.7 mm) long, and it weighs 13.2 oz (373 g). The front accepts screw-in filters directly, on a 67mm thread, so a directly attached filter must match that size.

At 20mm on full frame, this lens takes in wide scenes without stepping back. That suits grand landscapes, building interiors and courtyards where space is tight. It also frames broad night skies, with room for a foreground below the stars. Working close at 20mm exaggerates perspective, making near objects loom and distant ones recede.

The f/1.8 maximum aperture is bright for a wide prime. After sunset or inside a dim church, it gives you more room to keep shutter speeds usable without raising ISO as far. For night skies, it gathers more light than a smaller aperture, which can help limit exposure time before stars trail.

Manual focus reaches 0.6 ft (18 cm), measured from the sensor, for close foreground details such as rocks or flowers. Maximum magnification is 0.22x in that mode. Autofocus has a slightly longer minimum distance and a lower maximum magnification. Move carefully because the front glass sits closer than the sensor.

Stopping down and focusing farther away can keep more of a landscape sharp. At f/1.8 and close distances, however, this lens can still blur the background strongly. Choose aperture and focus distance to suit the balance between foreground detail and distant context.

The dust- and moisture-resistant design suits outdoor use in changing conditions. It is not waterproof, so use cover in heavy rain and avoid splashing water onto the lens.

A fluorine coating on the front element helps water and oil slide off. After a dusty track or a damp evening, the glass wipes clean without much rubbing.

There is no image stabilisation in the lens. A steady hold, faster shutter speed, body stabilisation or firm support can help, depending on the camera and subject. Long night exposures still benefit from a tripod. The features specification scores 52 of 100.

The design uses 14 elements in 12 groups, including two advanced aspherical elements and three ED elements. Aspherical surfaces help correct distortion, useful when straight building edges fill the frame. ED glass helps reduce coloured fringes along high-contrast edges. Internal focusing keeps the barrel length fixed as focus changes.