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)

Ergonomics

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.

Focusing

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.