Viltrox PFU RBMH 85mm f/1.8 STM (Fujifilm X) - Test Report / Review
Lens Reviews - Fujifilm X

Review by Klaus Schroiff, published January 2020

Introduction

Let's start 2020 with something different - the Viltrox PFU RBMH 85mm f/1.8 STM - and something new - our shift to a 26-megapixel test camera (X-T30). While most are probably familiar with the Fujifilm camera, the Viltrox lens may be a bit of an unknown factor for most. If you came across the Viltrox brand so far (if ever), it was probably about accessory items such as adapters or lighting solutions. However, since late 2018 they have been offering lenses as well. Now there are many new Chinese players out there these days and you may think that this is just another one but there is something special about Viltrox or at least the 85mm f/1.8 - it features an autofocus motor, a camera-controlled aperture as well as EXIF data so it can actually be regarded as a mainstream offering. It is also readily available from big shops such as B&H, Adorama or Amazon for as little as 399USD/379EUR - who said that mirrorless lenses have to be expensive? It's also worth mentioning that this is actually a full-format lens - the E-mount variant is compatible with Sony's full format cameras.

The build quality is pretty impressive thanks to a tightly assembled all-metal body. You can also feel it because the lens is rather heavy at 636g. The physical length remains constant across the focus range. The huge, fluted focus ring operates smoothly. Weather-sealing is, unfortunately, not provided but you can't have it all at this price point. The Viltrox lens doesn't participate in Fujifilm's own firmware update procedures but uses a Micro-USB connector on the lens for this purpose instead. A petal-shaped (plastic) lens hood is provided.

One of the biggest question marks may about the performance of the autofocus motor. After all, it is unusual for such a new player to offer a fully-coupled lens. The Viltrox lens uses an STM (or stepping motor). The AF is fast but you won't use it for sports/action photography in low light (which is where Fuji cameras still struggle anyway). Manual focusing works - as usual - "by wire" thus you are driving the AF motor when turning the focus ring. The focus action is pretty precise and as good as on Fujifilm's own lenses.

Specifications
Equivalent focal length (full-format)"127mm"
Equivalent aperture (depth-of-field, full-format)"f/2.7"
Optical construction10 elements in 7 groups inc. 1xELD element
Number of aperture blades9
min. focus distance0.8m (max. magnification 1:8)
Dimensions80×92mm
Weight636g
Filter size72mm
Hoodbarrel-shaped (bayonet mount, supplied)
Other featuresMicro-USB connector for firmware updates
MountsFujifilm X, Sony E