Sony E Autofocus

Viltrox AF 9mm F2.8

Focal length: 9 mm
Aperture: f/2.8
Weight: 175 g
Filter diameter: 58 mm
Min. focus distance: 13 cm
Length: 56.4 mm

Overview

The Viltrox AF 9mm F2.8 Air is an ultra-wide autofocus prime for APS-C mirrorless cameras with Sony E, Nikon Z or Fujifilm X mount. According to Viltrox it gives a 113.8 degree field of view, about 13.5mm on full frame. It is meant for landscapes, interiors, group selfies and vlogging.

Optical design

Viltrox specifies 13 elements in 11 groups with 2 aspherical, 3 ED and 3 high refractive index elements, plus coatings against glare and ghosting. The aperture runs from F2.8 to F16 with 7 blades. The minimum focus distance is 0.13 m at a maximum magnification of 0.15x. The lens is designed for APS-C sensors only.

Autofocus and handling

Focusing uses an STM stepping motor with a lead screw and internal focusing. Viltrox lists eye and face detection and minimal focus breathing, which it also recommends for focus stacking. There is no stabilizer in the lens. A USB-C port is used for firmware updates, and manual focus is available.

Build and size

The weight is 175 g on Sony E and Fujifilm X and 190 g on Nikon Z. The diameter is 65 mm, and the length is 56.4 mm on E, 56.7 mm on X and 58.4 mm on Z. The filter thread measures 58 mm, so standard screw-in filters can be used. Viltrox describes a sealed body, a metal mount and a front element with a water- and dirt-resistant coating.

Where it fits

The 9mm is the widest lens of Viltrox's APS-C Air series, which also includes the AF 15mm F1.7 and AF 25mm F1.7. Direct rivals in the same angle of view are the Venus Laowa 9mm F2.8 Zero-D, which is manual focus, and, for Fujifilm X, the Fujifilm XF 8mm F3.5 R WR. Slightly less wide zoom and prime alternatives include the Sigma 10-18mm F2.8 DC DN on Sony E and Fujifilm X, and the Sony E 11mm F1.8.

Pros and cons

Pros

113.8 degree field of view with an F2.8 aperture
Only 175 to 190 g
Close focus at 0.13 m
58 mm filter thread
Sealed body and coated front element according to Viltrox

Cons

No in-lens stabilization
Slower than the Sony E 11mm F1.8, which is somewhat less wide
7 aperture blades
Covers APS-C only

Verdict

The AF 9mm F2.8 Air is a pocketable ultra-wide for APS-C cameras with a bright aperture for its class. Photographers who need more flexibility in framing may prefer an ultra-wide zoom, while those who want a small prime will find this a convincing option.

Technical Specifications

min focal length: 9 mm
max focal length: 9 mm
max f (min zoom): f/2.8
max f (max zoom): f/2.8
min. aperture: f/16
Elements: 13
Groups: 11
Weight: 175 g (0.39 lb)
Filter diameter: 58 mm
min focus distance: 13 cm (5.12 in)
Length: 56.4 mm (2.22 in)
Diameter: 65 mm (2.56 in)

Simulate depth of field and angle of view

Which cameras does the Viltrox AF 9mm F2.8 fit?

The Viltrox AF 9mm F2.8 is designed for APS-C sensors. On APS-C Sony E-Mount cameras its field of view equals 14 mm in full-frame terms. Full-frame bodies use it in APS-C (crop) mode, recording only part of the sensor and fewer megapixels.

Sony E-Mount cameras

Full frame (in APS-C mode):: Sony A7R VI, Sony A7 V, Sony FX2, Sony A1 II, Sony A9 III, Sony A7C II, Sony A7CR, Sony ZV-E1, Sony A7R V, Sony A7 IV, Sony A1, Sony FX3, Sony A7S III, Sony A7C, Sony FX6, Sony A7R IV, Sony A9 II, Sony FX9, Sony A7 III, Sony A7R III, Sony A9, Sony A7R II, Sony A7S II, Sony A7 II, Sony A7S, Sony A7, Sony A7R
APS-C:: Sony ZV-E10 II, Sony A6700, Sony FX30, Sony ZV-E10, Sony A6600, Sony A6100, Sony A6400, Sony A6500, Sony A6300, Sony A6000, Sony A5100, Sony A5000, Sony A3000, Sony NEX-5T, Sony NEX-3N, Sony NEX-6, Sony NEX-5R, Sony NEX-F3