First Impressions: Viltrox PFU RBMH 20mm f1.8 ASPH (Sony FE)

Chinese photography accessories maker Viltrox is expanding their portfolio with brand new camera lenses

When Viltrox extended an invitation for us to check out their brand new line of lenses at this year’s Photo Plus Expo, our interest was certainly piqued. Up until this point, China-based Viltrox’s focus has been on the manufacturing of photography accessories like lens mount adapters, external monitors, speedlights, and LED lighting. We were quite eager to see how they fared with their first foray into lens manufacturing. As of right now, all of the lenses that Viltrox is working on are designed for Fujifilm and Sony mirrorless camera systems, which includes the Viltrox PFU RBMH 20mm f1.8 ASPH (Sony FE, manual only), Viltrox PFU RBMH 85mm f1.8 (Sony FE, manual only), and the Viltrox PFU RBMH 85mm f1.8 STM (Fuji X and Sony FE, autofocus).

At their booth at Photo Plus, Viltrox had both the 20mm and 85mm Sony FE manual lenses as well as the Fuji X mount version of the autofocus 85mm STM lens on display, with the manual lenses being the only functional prototypes. Viltrox’s explained that the we should expect the finalized version of the autofocus Fuji lens by the end of this year, with the Sony version arriving sometime during Q1 of 2019. Due to our extremely packed schedule at Photo Plus, we only got to spend some very limited hands on time with the prototype lenses, this first impressions article will focus on the Viltrox PFU RBMH 20mm f1.8 ASPH manual focus prime lens for Sony E-Mount.

Gear Used

We tested the Viltrox PFU RBMH 20mm f1.8 ASPH (Sony FE) using the Sony A7R II.


Tech Specs

Tech specs for the Viltrox PFU RBMH 20mm f1.8 ASPH (Sony FE) was taken from Viltrox’s marketing pamphlet

FocaI Length 20 mm
Aperture f1.8 – f16
Aperture Blades No. 14
Camera Mount Sony FE-Mount
Format Compatible Frames Full Frame
Shooting Distance 0.25 m (9.84″) – ∞
Field Angle (Diagonal / Horizontal / Vertical) 94°12′ / 75°22′ / 56°31′
Focus Mode MF (IF)
Image Field Diameter 43.2 mm (1.7″)
Close Range Coverage 199 x 299 mm (7.8 x 11.77″)
Image Ratio at Min. Distance 1:8.3
Lens Structure 12/9
Flange Distance 18 mm (0.71″)
Pupil Position (Image Surface Benchmark) 87.6 mm (3.45″)
Auto Focus – –
Image Stabilization – –
Auto Iris – –
EXIF Information – –
Filter Specification M82 x 0.75
Rotation Angle of the Focusing Ring 148.5°
Max. Diameter 76.8 mm (3.02″)
Diameter of the Focusing Ring 72 mm (2.83″)
Length (with Lens Cap) 123 mm (4.84″)
Length (without Lens Cap) 102 mm (4.02″)
Weight 775 g (1.71 pounds)



Here is one of the Viltrox PFU RBMH 20mm f1.8 ASPH prototypes on display at Viltrox’s booth at Photo Plus this year. Beginning from the front of the lens, you will find the detachable lens hood. Moving further back, first you will find the model number of the lens etched onto the top of the lens barrel, followed by the aperture ring, and then finally the manual focus ring as well as the depth of field scale. The Viltrox PFU RBMH 20mm f1.8 ASPH has a maximum aperture of f1.8 and can be stopped down to a minimum of f16.

Here is a look at the side profile of the Viltrox PFU RBMH 20mm f1.8 ASPH. Coming in 4.02″ long (not including the detachable lens hood) with a diameter of 3.02″, it’s nearly identical to Sony’s own 24mm f1.4 G Master in terms of diameter, but is about 1/4″ longer and weighs nearly 3/4 pounds more.

Here’s a look at the front of the Viltrox PFU RBMH 20mm f1.8 ASPH when mounted onto a Sony A7 III.

Clearly labeled around the front element of the front of the Viltrox PFU RBMH 20mm f1.8 ASPH (with lens hood attached) are the model number of the lens as well as the filter thread diameter (82mm).


Build Quality

Designed for Sony Full Frame mirrorless cameras, the Viltrox PFU RBMH 20mm f1.8 ASPH is a manual focus prime lens that features a whopping 14 bladed “hypercircle” aperture design, and is housed within a precision crafted brass enclosure. The lens features an optical design that consists of nine lens groups with twelve optical elements, including a large diameter double-sided aspherical front element, four ED (Extra-low Dispersion) glass elements, as well as a low wave high transparency glass element. The optical elements are coated with what Viltrox calls “HD Nano multilayer” coating, with the front element being waterproof and fog resistant. While we only got to spend a very limited amount of time with the Viltrox PFU RBMH 20mm f1.8 ASPH at Photo Plus, the lens felt well constructed overall. We didn’t run into any issues when attaching and removing the lens on our own Sony A7R II, and the aperture ring and manual focus ring both felt very smooth during our brief time testing the lens.



As we had previous stated, the Viltrox PFU RBMH 20mm f1.8 ASPH is a fully manual focus prime lens. If you’re one of the photographers out there that has manual-focus-phobia, this is definitely not the lens for you. Those of you that aren’t allergic to manual focus will find the Viltrox PFU RBMH 20mm f1.8 ASPH to be a fairly user friendly lens. With a built in depth of field scale, as well as focus peaking and zebra being available via your camera’s EVF or live view, it’s really not that hard to nail focus using this lens.


Image Quality

Due to our overwhelming schedule at Photo Plus this year, we literally only got to spend a few minutes with the Viltrox PFU RBMH 20mm f1.8 ASPH lens. Here are a few images that we shot using this lens paired with our own Sony A7R II.


Ease of Use

Like most manual focus lenses, the Viltrox PFU RBMH 20mm f1.8 ASPH (Sony FE) is fairly easy to use. Aperture value as well as focusing are controlled using their respective manual control rings, both of which felt buttery smooth during our limited time with the lens. If you’re one of the photographers that like to keep meticulous metadata records, note that the Viltrox PFU RBMH 20mm f1.8 ASPH does not transmit any EXIF data, so you’ll want to record your settings manually when using this lens.


First Impressions

While we only got to spend some very limited time with the Viltrox PFU RBMH 20mm f1.8 ASPH (Sony FE) lens, the lens felt reasonably well built overall. At press time, pricing and availability are TBD. We will be receiving a review unit of the Viltrox PFU RBMH 20mm f1.8 ASPH (Sony FE) later this year, and we look forward to evaluating this lens in depth upon its arrival. Please stay tuned for the full review.

Pauleth Ip

Paul is a New York City based photographer, creative, and writer. His body of work includes headshots and commercial editorials for professionals, in-demand actors/performers, high net worth individuals, and corporate clients, as well as intimate lifestyle/boudoir photography with an emphasis on body positivity and empowerment. Paul also has a background in technology and higher education, and regularly teaches private photography seminars. When not working on reviews and features for The Phoblographer or shooting client work, Paul can be seen photographing personal projects around NYC, or traveling the world with his cameras in tow. You can find Paul’s latest work on his Instagram over at @thepicreative.