Introduction

Ease of Use

Given the extremely wide zoom range on offer, the Tamron 50-400mm F/4.5-6.3 Di III VC VXD is unsurprisingly a rather large and rather heavy lens, measuring 18.3cms in length and weighing in at well over 1kg - 1,155g / / 40.7 oz to be precise.

If you consider that it is very similar in size and weight to a typical 70-200mm f/2.8 or the more usual 100-400mm zoom, though, with much less lens swapping needed due to the wider 50mm focal length, then this lens suddenly becomes a lot more desirable.

While you can use it on a smaller APS-C body like the Sony A6000 series of cameras, it won't balance particularly well and the equivalent focal length will also change to 75-600mm (which may be a benefit).

As demonstrated by the product images, it's a much better match for a more professional full-frame camera like the Sony A7R IV that we tested it with, where it just feels better balanced and more "at home".

Build quality is excellent, despite Tamron traditionally offering lenses at the cheaper end of the market. The Tamron 50-400mm F/4.5-6.3 Di III VC VXD feels very solid in your hand, with the outer barrel made from high-grade plastics as in all of their recent lenses.

Compared to most previous Tamron lenses, though, the 50-400mm has a more glossy, shinier black finish, a redesigned pattern on the focus and zoom rings, and a more scratch and fingerprint resistant exterior.

The Tamron 50-400mm F/4.5-6.3 Di III VC VXD feels solid enough in your hand, despite its mostly polycarbonate construction. It has a metal lens mount.

The zoom ring is more than wide enough, offers a smooth action with a relatively short 75 degree throw, and has a tactile ridged and rubberised grip band.

Note that the lens extends by about an extra 7.5cm when fully zoomed out to 400mm, though, which does make it rather conspicuous.

The 50-400mm F/4.5-6.3 Di III VC VXD features a Lock switch which fixes the lens at its 50mm setting and prevents it from extending when it's pointed downwards, although we didn't really notice any significant zoom creep.

There is one focus control button, a feature that is found on many other Tamron zooms. The function of this button can be customised via the Custom switch, which offers 3 presets that are configurable using the Lens Utility software.

The other significant new feature is the USB-C Connector Port, which allows you to update and customise the lens directly using the Tamron Lens Utility software, rather than via a camera body.

We are a little concerned that this port is uncovered, though, and therefore not protected from the elements, although Tamron have assured us that it is fully waterproof.

In the customisation options, the direction and speed of focus can be changed. The focus ring can be used for aperture instead of manual focusing, while the focus hold button can be customised for a preset focus point for video so that you can pull focus from one to the other at a designated speed.

A new Focus Limiter control feature is also now available for this lens in the TAMRON Lens Utility software.

The focusing ring is located towards the end of the lens mount, which is the reverse of the 28-75mm F2.8 Di III VXD G2 that we recently reviewed, making it slightly unintuitive and harder to locate in a rush.

The Tamron 50-400mm F/4.5-6.3 Di III VC VXD features the latest high-speed VXD (Voice-coil eXtreme-torque Drive) which is said to be twice as fast as the older RXD motors. It also allows for virtually silent auto-focusing, making it well-suited to video use.

In use, we found the VXD focusing system to be whisper quiet and very fast with the lens mounted on a Sony A7R IV camera.

Importantly, the lens is fully compatible with the "Direct Manual Focus (DMF)" system feature of Sony cameras that enables the user to instantly switch between autofocus and manual focus.

Focusing is fully internal but zooming is not, with the length of the lens gradually increasing by up to a maximum of 7.5cm as you zoom from 50mm to 400mm.

The Tamron 50-400mm F/4.5-6.3 Di III VC VXD isn't fully weather-proof but it does benefit from a moisture-resistant construction with 8 internal seal points and a rubber gasket around the mount.

This helps to prevent moisture from penetrating the lens, although we'd hesitate to use it in heavy rain for a prolonged period of time without some protection.

The front element has a hydrophobic Fluorine Coating that is highly resistant to fingerprints and debris.

The VC Mode switch controls Vibration Compensation, with three different options - Off, 1 (standard) and 2 (dynamic).

Note that turning off vibration compensation via the lens automatically disables the in-camera IBIS, and turning off IBIS via the camera body automatically disables the vibration compensation via the lens, even if the switch is set to mode 1 or 2.

The lens is supplied with plastic lens caps and a plastic petal-shaped lens hood (HA067) which twists and lock into place - there's no lens bag included.

The filter size is an economical 67mm. Note that this lens is not compatible with either Tamron's or Sony's range of 1.4x or 2x teleconverters.

On a more positive note, there is an official tripod collar/mount available for this lens, the Tamron A035TM, which is compatible with most Arca-type heads and clamps.

Unfortunately it's a rather expensive optional accessory (£/109 / $129) that we feel should have been included in the box.

Focal Range

At the 50mm focal length the angle of view is 46°48' degrees.

50mm

At the 400mm focal length the angle of view is 6°11' degrees.

400mm

Chromatic Aberrations

Chromatic aberrations, typically seen as purple or blue fringes along contrasty edges, are well controlled with this lens.

50mm

400mm

Vignetting

With the Tamron 50-400mm F/4.5-6.3 Di III VC VXD wide open, you can see some noticeable light fall-off in the corners. Stopping down helps, although to completely get rid of this phenomenon, you will need to use an f-stop of f/11 or smaller.

50mm

400mm

Distortion

There's quite a lot of pin-cushion distortion evident in both the JPEG and RAW files which you'll need to correct in post-processing until a suitable lens profile is released for your editing software.

50mm

400mm

Sunstars and Flare

The Tamron 50-400mm F/4.5-6.3 Di III VC VXD produces quite nice sunstars when stopped-down to f/22-f/32, as shown below, although it it a little prone to flare when shooting directly into the sun.

50mm

50mm

200mm

400mm

Macro

The Tamron 50-400mm F/4.5-6.3 Di III VC VXD very usefully doubles up as a half-life-size macro lens (at 50mm), delivering good performance throughout the zoom range.

The close-focus point is an impressive 25cm / 9.8in from the film/sensor plane at the 50mm focal length and 1.5m / 59.1in at 400mm.

It has a maximum magnification ratio of 1:2 at the 50mm focal length and 1:4 at 400mm.

50mm

400mm

50mm

400mm

Bokeh

Bokeh is a word used for the out-of-focus areas of a photograph, and is usually described in qualitative terms, such as smooth / creamy / harsh etc.

In the 50-400mm F/4.5-6.3 Di III VC VXD lens, Tamron have employed an iris diaphragm with 9 rounded blades, which combined with the longer focal lengths results in very nice bokeh in our view.

We do realise, however, that bokeh evaluation is subjective, so we've included lots of examples below for your perusal.

50mm

50mm

400mm

400mm

Sharpness

In order to show you how sharp the Tamron 50-400mm F/4.5-6.3 Di III VC VXD lens is, we are providing 100% crops on the following pages.