Nikon AF-S NIKKOR 20mm f/1.8 G ED Autofocus Lens {77}

Nikon's 20mm f/1.8G ED: the ultrawide prime that works after dark.

A 94-degree field of view at f/1.8 is a combination that opens up shooting scenarios most ultrawides can't touch. Landscapes, interiors, astrophotography, event work in dim venues, the f/1.8 aperture lets you keep ISO in check where slower glass forces you to compromise. At 12.6 oz on a Nikon F mount body, this is a lens that doesn't demand a dedicated bag slot.

Optically, the 13-element, 11-group design combines aspherical elements with ED glass to handle the two problems that plague fast ultrawides: spherical aberration and chromatic fringing. Nano Crystal Coat and Super Integrated Coating work together to kill flare and ghosting, which matters enormously when you're shooting into light sources at wide angles. The Silent Wave Motor delivers AF that's fast and quiet enough for video work, and full-time manual override means you're never fighting the lens for control.

On FX bodies, you get the full 94-degree angle of view. On DX, it shifts to a 70-degree, 30mm-equivalent perspective, still an useful wide, with the same optical quality. The 7.9-inch minimum focusing distance lets you push foreground subjects into the frame without backing off, an useful tool for adding depth to architectural and landscape compositions. This is a mature, prime that Nikon got right.

Who It's For

Astrophotographers benefit directly from the f/1.8 aperture across a 94-degree sky, pulling in more light per frame than any f/2.8 ultrawide can match. Architecture and interior photographers will use the 20mm perspective to work tight rooms without distortion piling up, thanks to the aspherical elements in the optical design. Documentary and event shooters working in low-light venues get AF that's quiet enough for video and fast enough for candid moments. Landscape photographers pushing foreground-to-background depth will find the 7.9-inch minimum focus distance gives them close subject options that a typical ultrawide prime doesn't allow.

Key Features

• 20mm focal length with 94-degree field of view on FX bodies
• f/1.8 maximum aperture for low-light performance and shallow depth of field
• 13-element, 11-group design with aspherical and ED glass
• Nano Crystal Coat and Super Integrated Coating reduce flare and ghosting
• AF-S Silent Wave Motor for fast, quiet autofocus with full-time manual override
• 12.6 oz weight with 3.1" length, compact enough for any bag

FAQ

What makes the 20mm f/1.8G useful for astrophotography compared to slower ultrawides?

The f/1.8 aperture gathers roughly 2.8 times more light than an f/2.8 ultrawide, letting you hit shutter speed thresholds for star trails or nebulae without pushing ISO into visible noise. Combined with the 94-degree field of view, you're capturing sky across a wider area at cleaner ISOs.

How does this lens perform on DX-format bodies?

On DX sensors, the 20mm becomes a 30mm-equivalent focal length with a 70-degree angle of view. You lose the extreme ultrawide perspective, but the optical quality and f/1.8 aperture remain unchanged - useful for tighter interiors or event work where you need some standoff distance.

Can you use this lens for video work?

Yes. The AF-S Silent Wave Motor delivers quiet, smooth autofocus that won't record as a focus-hunting hum in your audio. The fast f/1.8 aperture keeps exposure stable in variable lighting during handheld run-and-gun shooting, and full-time manual focus override means you can rack focus manually without disengaging the motor.

What's the purpose of the aspherical and ED elements?

The aspherical elements correct spherical aberration, which causes softness and contrast loss across the frame edges at ultrawide focal lengths. The ED glass handles chromatic fringing, the color separation that appears as colored fringes on high-contrast edges. Together they eliminate the optical compromises that plague cheaper ultrawides.

How close can you focus, and does that change the perspective?

Minimum focusing distance is 7.9 inches. This rear-focus design means the lens doesn't extend as you focus, and the short minimum distance lets you position strong foreground subjects close to the lens while keeping background scale visible - essential for landscape depth.

What do the Nano Crystal and Super Integrated Coatings do?

Both are anti-reflective coatings that suppress internal reflections. At 20mm with a fast aperture, you're shooting into light sources constantly - sun near the horizon, stage lights, street lamps. These coatings kill flare and ghosting that would otherwise degrade contrast and introduce unwanted shapes in your frame.

Is this lens weather-sealed?

No. The AF-S NIKKOR 20mm f/1.8G has no gaskets or protective sealing, so treat it like any standard FX prime - avoid prolonged moisture exposure and use lens caps and filters as your first defense against weather.