Viltrox AF 25mm F1.7

The Viltrox AF 25mm F1.7 is an autofocus prime lens for APS-C mirrorless cameras with Sony E, Fujifilm X or Nikon Z mount. It belongs to Viltrox's Air series of small, light lenses. According to Viltrox's own lens table it gives a view like roughly 37.5mm on full frame, a natural perspective that suits street photography, everyday shooting and indoor scenes.

Optical design

Viltrox specifies 12 elements in 10 groups, including 1 ED, 2 high refractive index and 2 aspherical elements, plus an HD nano multi-layer coating. The aperture runs from F1.7 to F16 and has 9 blades, which the manufacturer says gives round bokeh. The minimum focus distance is 0.3 m at a maximum magnification of 0.11x. The image circle covers APS-C only.

Autofocus and handling

Focusing is driven by an STM stepping motor with a lead screw and uses internal focusing. Viltrox lists eye and face detection and describes focus breathing as minimal for video work. There is no stabilizer in the lens. For video Viltrox points to the in-body stabilization of the camera, so the lens depends on the body for that. Manual focus is available as well.

Build and size

The lens measures 64 mm in diameter and 56.4 mm in length on all three mounts. The weight is 170 g for Sony E and Fujifilm X and 180 g for Nikon Z. It takes 52 mm filters. Viltrox does not list weather sealing for this lens, so it is best treated as a lightweight everyday lens rather than a rugged one.

Where it fits

Within the Air series the 25mm sits between the wider AF 15mm F1.7 and the AF 35mm F1.7. For more light and a slightly wider view, the Viltrox AF 23mm F1.4 and the Sigma 23mm F1.4 DC DN Contemporary are the obvious faster alternatives. Fujifilm X users can compare the Fujifilm XF 23mm F2 R WR and the Fujifilm XF 27mm F2.8 R WR. For Nikon Z there is the Nikon Nikkor Z DX 24mm F1.7 as a native alternative.

Pros and cons

Pros

• Bright F1.7 aperture in a body of only 170 to 180 g
• Close focus at 0.3 m
• STM autofocus with eye and face detection
• 9 aperture blades
• Available for three APS-C systems with the same 52 mm filter size

Cons

• No in-lens stabilization
• Viltrox lists no weather sealing
• Slower than F1.4 alternatives such as the Viltrox AF 23mm F1.4
• Covers APS-C only

Verdict

The AF 25mm F1.7 is a small, bright standard prime for APS-C users who want to keep their kit light. Those who need weather resistance or an even larger aperture will find more suitable options in the F1.4 class.