Viltrox PFU RBMH 20mm f/1.8 ASPH (Sony FE) - Test Report / Review
Lens Reviews - Sony Alpha (Full Format)

Review by Klaus Schroiff, published January 2020

Introduction

In our previous review, we covered the Viltrox PFU RBMH 85mm f/1.8 STM (in Fujifilm X mount) and we were quite impressed by it. They are about to release more AF lenses in 2020 but they also have an ultra-wide prime lens in their lineup - the Viltrox PFU RBMH 20mm f/1.8 ASPH, an all-manual lens without electronic coupling, unfortunately. Generally, this shouldn't be a huge deal with a 20mm lens and if needed you can use a magnified focus view on your camera for precise manual focusing. It is limiting the target audience for sure but moviemakers will actually prefer the all-manual nature - also because Viltrox implemented a step-less aperture ring.

The Viltrox lens feels like being carved out of a solid piece of metal and it is about as heavy (775g). The focus and aperture control rings are super-smooth and dampened just like in the good ol' days. The lens uses an internal focusing mechanism thus the length remains constant throughout the focus range. The front element is bulb-like as you can see below so it's not possible to mount filters straight on the lens. However, Viltrox found a curious workaround for this. Besides the (plastic) petal-shaped lens hood, they provide a 2nd (metal) barrel-shaped one. It's rather tiny but you can mount 82mm filters to it. While the lens construction is of very high quality, we can't say the same about the lens cap (for the standard hood) which feels a bit cheap and flimsy.

EXIF data is not provided so mechanisms such as image auto-correction. In-camera image stabilization is possible when setting the focal length manually to 20mm - we used this approach for the sample images actually.

Specifications
Optical construction12 Elements in 9 Groups inc. 1xaspherical & 4xELD elements
Number of aperture blades14
min. focus distance0.25m (max. magnification 1:8.3)
Dimensions76.8x102mm
Weight775g
Filter sizeno native filter thread (82mm on the hood)
Hoodpetal- & barrel-shaped (bayonet mount, supplied)
Other featuresstepless aperture ring
MountSony FE