Samyang AF 12mm f/2

This Samyang AF 12mm f/2 is an ultra-wide prime for Canon RF-S APS-C cameras. It suits anyone shooting architecture, room interiors, landscapes or the night sky. At 12mm it frames whole rooms and broad buildings from a single position, and the f/2 aperture keeps the lens working after dark.

The main trade-off is the fixed focal length. You frame by moving closer or stepping back, not by zooming, so it rewards planning over speed. The lens arrived in 2024 and remains in production, and it covers APS-C sensors rather than full frame.

The lens weighs 7.5 oz (213 g) and measures 2.76 in (70 mm) across and 2.25 in (57.2 mm) long. That keeps it light on a compact APS-C body for travel and long walks. The front takes screw-in filters, which must match the 62mm thread on the lens. A polariser on that thread can darken blue sky in daylight landscapes.

On an APS-C sensor, 12mm gives a very wide view. Indoors it can frame a full room from one corner. Outdoors it takes in wide buildings, streetscapes and open landscapes in a single shot. Distant people and objects shrink quickly at this width, so a strong foreground gives the picture structure.

The f/2 maximum aperture matters most in dim light. The wide opening gathers light for dim interiors, evening streets and night skies. For star photography, that extra light helps keep shutter speeds short enough that stars record as points rather than trails.

Minimum focus sits at 0.7 ft (20 cm). That lets you place a rock, flower or doorway close to the camera and still keep the whole scene in frame. Working near a foreground object at 12mm creates a strong sense of depth.

Framing is fixed at 12mm. You cannot tighten the shot by zooming, only by walking toward the subject. Seven aperture blades influence how out-of-focus highlights appear once the lens stops down.

The lens is weather sealed, so dust and moisture are less likely to reach the interior during outdoor shoots. That fits its likely use, since landscapes, architecture and night-sky sessions often mean standing outside for long periods in changing conditions.

There is no built-in image stabilization. Camera shake matters less at 12mm than at longer focal lengths, so the gap is smaller here than it would be on a telephoto. Still, you may notice it during long handheld exposures at dusk.

The glass has no fluorine coating. Without that water- and oil-repelling layer, dust spots and rain marks on the front element may need more patient cleaning after outdoor work.

The optical path holds twelve elements in ten groups. Two aspherical elements help correct distortion and spherical aberration. That matters for architecture, where distortion can curve straight walls.

Three low-dispersion elements help reduce chromatic aberration, where colours focus differently and leave coloured fringes. Those fringes tend to appear along high-contrast edges, such as bright stars against a dark sky.