Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon Review
The Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon is the only 70-300mm, 4.3x telephoto zoom lens currently available for Nikon's range of full-frame mirrorless cameras.
The Tamron 70-300mm for Nikon features an RXD stepping focus motor for quiet and fast AF operation and a moisture-sealed construction.
The optical formula is comprised of 15 elements in 10 groups, including one low dispersion front element, and it has an iris diaphragm with seven rounded aperture blades.
It has a customizable focus/function ring that can be used to control either aperture, exposure compensation or ISO speed.
The Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon lens is priced at around £649.99 / $599.99 in the UK and USA respectively, and it is made in China.
Note that this lens is not compatible with Nikon’s Z TC-1.4x and Z TC-2.0x teleconverters.
Ease of Use
Given the 300mm maximum telephoto reach, the Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon is a surprisingly lightweight and compact lens.
It measures almost 15cms / 5.8" in length, although it does extend by about an extra 6cm when fully zoomed out to 300mm.
It weighs in at only 580g / 1.2lb, which is 35g more than the Sony E-mount version. Optically the two versions of this lens are identical.
You can also use it quite effectively on a smaller APS-C body like the Nikon Z50 / Z30 / Zfc cameras, where the equivalent focal length will change to 105-450mm.
There isn't really a direct like-for-like rival to the Tamron 70-300mm F4.5-6.3 Di III RXD in the current Nikon lens range. You could consider either the Nikon Z 100-400mm f/4.5-5.6 VR S or the Nikon Z 70-200mm f/2.8 VR S zooms, but they're both larger, heavier and much more expensive.
Build quality is fine, but not quite as good as past Tamron "SP" branded lenses that we've previously reviewed.
The Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon feels solid enough in your hand, thanks to its high-strength aluminum-magnesium alloy construction.
The zoom ring is very wide and has a ridged, rubberised grip band. There is no useful focus lock switch as found on many other Tamron zooms, which is a shame as the lens is susceptible to zoom creep.
Note that the zoom ring is rather unusually in front of the focus ring, which initially proved to be somewhat counter-intuitive.
The focusing ring is much narrower than the zoom ring, making it more difficult to locate in a rush.
Importantly, full-time manual focus override is also possible which enables the user to instantly switch between autofocus and manual focus by simply turning the focus ring.
The focus ring can also optionally be assigned in-camera to operate the aperture, exposure compensation or ISO sensitivity, much like the multi-function control ring on some of Nikon's Z lenses, but then you obviously lose the ability to manually focus the lens.
Focusing is fully internal but zooming is not, with the length of the lens changing as you zoom from 70 to 300mm.
The Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon features a high-speed RXD (Rapid eXtra-silent stepping Drive) motor unit that allows virtually silent auto-focusing, making it well-suited to video use.
In use, we found the auto-focus system to be very quiet and satisfyingly fast with the lens mounted on a Nikon Z9 camera, although not quite as snappy as Nikon's comparable native lenses.
The Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon isn't fully weather-proof, but it does benefit from a moisture-resistant construction which helps to prevent moisture from penetrating the lens, although we'd hesitate to use it in the rain for a prolonged period.
This lens is fully compatible with Nikon's in-camera shading, chromatic aberration and distortion lens correction functions.
There is no stabilization built into this lens, instead it relies on the sensor-based stabilization of the camera body (if available).
The lens is supplied with plastic lens caps and a plastic circular lens hood that clicks into place - there's no lens bag included. The filter size is an economical 67mm.
At the 70mm focal length the angle of view is 34°21'.
At the 300mm focal length the angle of view is 8°15'.
Chromatic aberrations, typically seen as purple or blue fringes along contrasty edges, are fairly well controlled with this lens.
With the Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon lens wide open at f/4.5 or f/6.3, you can see some obvious light fall-off in the corners at both ends of the zoom range. Stopping down helps, although to completely get rid of this phenomenon, you will need to use an f-stop of f/11 or smaller.
On the whole, distortion is very well-controlled at both ends of the focal range.
The Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon is not really a macro lens.
The close-focus point is 0.8m / 31.5inch from the film/sensor plane at 70mm and 1.5m / 59.1inch at 300mm, with a maximum reproduction ratio of 1:9.4 at 70mm and 1:5.1 at 300mm.
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.
Tamron have employed an iris diaphragm with seven rounded blades for a fairly pleasing rendering of the out-of-focus highlights.
Based on what we have seen, we can say that they have largely succeeded. Below you'll find some examples, but you are also encouraged to check out our Sample Images.
In order to show you how sharp the Tamron 70-300mm F4.5-6.3 Di III RXD for Nikon lens is, we are providing 100% crops on the following pages.