Nikon's modern nifty fifty with AF-S motor, the 50mm every Nikon shooter should own.
The Nikon AF-S Nikkor 50mm f/1.8G was released in 2011 as Nikon's mid-range FX normal prime, replacing the older AF Nikkor 50mm f/1.8D with an AF-S Silent Wave Motor design compatible with all Nikon F-mount bodies including those without an internal AF drive motor. At 185g and 58mm filter thread it is the lightest and most compact AF-S FX normal prime in the Nikon lineup, positioned below the f/1.4G. The AF-S motor makes it the standard 50mm recommendation for entry Nikon DX bodies without screwdrive AF.
The optical design uses 7 elements in 6 groups. Seven rounded aperture blades produce smooth bokeh. The 58mm filter thread is shared with several Nikon consumer and prosumer primes. At 185g the lens is very light. Minimum focus distance of 0.45m. AF-S SWM enables compatibility with D40/D40x and all later motorless Nikon bodies. No VR. Nano Crystal coating minimises ghosting and flare. Variable aperture operation from f/1.8 to f/16. Internal focusing type; constant barrel length.
The AF-S 50mm f/1.8G's primary practical advantage over the older f/1.8D is the AF-S motor: D40, D40x, D60, D3xxx, and D5xxx bodies that cannot drive screwdrive AF-D lenses can autofocus the f/1.8G natively. On FX bodies the 50mm is the classic normal perspective. The f/1.8 aperture provides subject separation and low-light capability at one full stop better than f/2.8 maximum aperture zooms. The 185g weight makes it the most practical standard prime for a lightweight Nikon kit.
On the used market the AF-S 50mm f/1.8G is widely available at very affordable prices — one of the most common Nikon primes. Condition checks: AF-S motor response for smooth acquisition, front element for marks, and overall barrel condition. The AF Nikkor 50mm f/1.8D is available at lower prices but requires a body with AF drive motor. The Nikon AF-S 50mm f/1.4G provides additional aperture at double the weight and price. Compatible with all Nikon F-mount bodies.