Yongnuo YN 50mm F1.8 DA DSM

Focal length: 50 mm
Aperture: f/1.8
Weight: 148 g
Filter diameter: 49 mm
Min. focus distance: 45 cm
Length: 58 mm

Overview

The Yongnuo YN 50mm F1.8 DA DSM is a very small autofocus prime for APS-C Nikon Z cameras. It frames like a 75 mm lens on full frame, which makes it a short portrait lens for DX bodies. Yongnuo lists it for the Z50 II, Z50, Z30 and Zfc, and notes that on full-frame Z bodies it works with an automatic crop.

Optical design

Yongnuo specifies 8 elements in 7 groups with an aperture range of f/1.8 to f/16 and seven aperture blades. One low-dispersion glass element is intended to suppress chromatic dispersion, and a nano-multilayer coating is meant to reduce ghosting and flare. The front element has a fluorine coating. The diagonal angle of view is about 30.4 degrees.

Autofocus and handling

A digital stepping motor (DSM) with internal focusing drives the focus. The minimum focus distance is 45 cm at 0.14x magnification. The lens has no aperture ring or wireless function in Yongnuo's data, so the aperture is set from the camera. A USB-C port allows firmware updates.

Build and size

The barrel has a metal bayonet with gold-plated contacts and a dust and splash resistant gasket at the mount. Yongnuo uses a spot-sprayed rear shell that is meant to reduce fingerprints. The filter thread is 49 mm. The lens measures about 64 x 58 mm and weighs about 148 g, according to Yongnuo's specification (one marketing graphic mentions about 134 g, so the exact figure may vary).

Where it fits

For Nikon Z DX bodies, the database lists the Nikon Nikkor Z DX 24mm F1.7 at a wider focal length, and the Viltrox AF 56mm F1.4 at a longer one. The Nikon Nikkor Z 50mm F1.8 S is a full-frame lens that can also be used on DX bodies and then gives the same 75 mm equivalent view. The Yongnuo is targeted at users who want a very light short tele portrait lens on a Z50 or Z30.

Pros and cons

Pros

About 148 g, very compact
f/1.8 aperture with a 75 mm equivalent view
Low-dispersion element and nano coating
USB-C firmware updates

Cons

APS-C only
45 cm minimum focus distance
No aperture ring or wireless remote
49 mm filters differ from the 52 and 58 mm sizes of other Yongnuo lenses

Verdict

The YN 50mm F1.8 DA DSM is a compact and light portrait-length prime for Nikon Z DX cameras. It suits users who want a bright 75 mm equivalent for everyday portraits without adding weight to a small camera.

Technical Specifications

min focal length: 50 mm
max focal length: 50 mm
max f (min zoom): f/1.8
max f (max zoom): f/1.8
min. aperture: f/16
Elements: 8
Groups: 7
Weight: 148 g (0.33 lb)
Filter diameter: 49 mm
min focus distance: 45 cm (17.72 in)
Length: 58 mm (2.28 in)
Diameter: 64 mm (2.52 in)

Simulate depth of field and angle of view

Which cameras does the Yongnuo YN 50mm F1.8 DA DSM fit?

The Yongnuo YN 50mm F1.8 DA DSM is designed for APS-C sensors. On APS-C Nikon Z cameras its field of view equals 75 mm in full-frame terms. Full-frame bodies use it in APS-C (crop) mode, recording only part of the sensor and fewer megapixels.

Nikon Z cameras

Full frame (in APS-C mode):: Nikon ZR, Nikon Z5II, Nikon Z6III, Nikon Z8, Nikon Zf, Nikon Z9, Nikon Z5, Nikon Z6II, Nikon Z7II, Nikon Z6, Nikon Z7
APS-C:: Nikon Z50II, Nikon Z30, Nikon Z fc, Nikon Z50