Canon RF 16-28mm f/2.8 IS STM review: does this make pricey, wide-angle trinity lenses redundant?

The Canon RF 16-28mm f/2.8 IS STM is a “never before seen” lens in either of the manufacturer's EF or RF ranges. The new optic follows on from 2024’s Canon RF 28-70mm f/2.8 IS STM, which was the company's first non-L-series lens to get premium features like weather-sealing. The new lens continues this tradition, and well-built and affordable lenses are great news for the consumer!

It doesn’t just share weather sealing with its spiritual sibling, though; they’ve been designed to work as a powerhouse pair of lightweight travel-friendly lenses. They have a similar weight and size, and share the same 67mm front filter thread, too, so they can be easily swapped on a gimbal, and lens filters can be interchanged without fuss.

The tagline for the new wide-angle zoom is “epic views, stable shots” – and this is clearly a reference to its super wide-angle full-frame focal length, ideal for cramming in large spanning vistas from landscapes, interior and big skies, and is stabilized too for sharp handheld photos and video.

In terms of stabilization, the Canon RF 16-28mm f/2.8 IS STM features Optical Image Stabilization that the manufacturer claims can deliver sharp shots at up to 5.5 stops slower than normal – and this is supercharged to up to 8 stops (7.5 in the corners) when paired with a stabilized EOS R body.

I got hold of a beta sample of the lens and, while I won’t be able to give my final verdict on image quality until we can run rigorous lab tests on a production version, I am very eager to see how it performs. I personally own the EF 16-35mm f/2.8L II, and use it on my newer EOS R bodies bodies via an adapter, so I reckon the Canon RF 16-28mm f/2.8 IS STM is aimed exactly at people in my position who are overdue for an upgrade.

Canon RF 16-28mm f/2.8 IS STM: Specifications

Canon RF 16-28mm f/2.8 IS STM: Design & Handling

The Canon RF 16-28mm f/2.8 IS STM is a similar size and weight to its sibling, the RF 28-70mm f/2.8. Weighing in at 445g and with dimensions of 76.5 x 91mm, the optics make a formidable tag team with versatile zoom ranges and a wide maximum f/2.8 aperture making them suitable for a huge breadth of subject matter.

The lens is portable and travel-friendly, partly due to its ‘popping’ design – which means the focus ring needs to first be twisted and ‘popped’ out to the 16mm mark before you can start shooting with the lens. This enables it to collapse down to just 91mm compared to the 126.8mm of the Canon RF 15-35mm f/2.8L IS USM, so it’s 28% smaller when stowed away. It’s also a whopping 47% lighter!

It’s a similar story with the older Canon EF 16-35mm f/2.8L III USM lens for DSLRs, too, though here Canon says it delivers comparable image quality. If these claims hold up (I’ll assess in more detail in Performance) it’s surely an impressive feat to pack great quality into a weather-sealed RF lens that is 43% lighter and 30% shorter when closed down than its DSLR counterpart. It’s also about 14% narrower, so it’s a very portable wide-angle zoom all-round.

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Despite being so compact, the wide-angle zoom packs in some impressive tech. This includes 5.5 stops of Optical Image Stabilization, boosted further to a whopping 8 stops when paired with an image-stabilized EOS R camera (up to 7.5 stops in the corners, via the new CIPA rating).

Its 9-bladed aperture is the same number as found in the RF 15-35mm f/2.8L trinity lens, and its optical construction appears similar with 16 elements in 13 groups, compared to the 16 elements in 12 groups on its more expensive sibling.

Canon says the lens has “maximum sharpness” with two aspherical lenses, one of which is a GMo (Glass Moulded) aspheric while the other is a replica aspheric. It also includes not one but four UD (Ultra-low Dispersion) elements for high quality, and a Super Spectra coating which Canon claims will produce “incredible clarity”.

The lens is very slim and doesn’t take up very much real estate when retracted. It’s even more low-profile for city shooters, too, as it omits the eye-catching red ring around the front of the lens found on Canon’s elite L-series lenses.

Making the lens so small and portable comes with a few concessions. The first is the aforementioned twist-to-pop design to begin shooting with the lens, which is a divisive design choice.

The other is that the knurled control ring at the front of the lens, used for quickly changing custom settings such as ISO or white balance, is also shared with the manual focus. A three-way switch needs to be used to toggle between AF, MF and control – there’s simply not enough real estate on the lens barrel to warrant a dedicated third adjustment ring like on the larger L-series iteration.

Besides that, the lens feels pretty solid, it has a plastic exterior barrel with a metal rear mount plate which helps keep the weight down and you’ll also see one of the weather seals around the rear mount, hinting that there are more seals inside around key areas such as the zoom and focus rings and switches. Speaking of switches, there is also one more switch to toggle the Stabilizer on and off.

Canon RF 16-28mm f/2.8 IS STM: Performance

Although I only had a beta sample of the lens to work with, I was initially impressed by the optic, particularly by all of the desirable features packed into such a small compact form. While the price of entry (£1249.99 in the UK) is no small chunk of change, I’m in favor of Canon keeping the cost low and features stacked high – it’s half the price of the RF 15-35mm f/2.8L.

Let’s start with the autofocus, as it blew me away with how snappy, smooth and quiet it was – it’s brilliant for both still photos and video. This is thanks to the special type of ‘lead-screw’ STM employed here, which is usually reserved for bigger lenses where these special stepping motors make autofocusing smoother and quieter.

The lens supports digital focus breathing correction and Canon claims that “the lens performs very well when switching focus between subjects at different distances”. Canon’s digital focus breathing was first employed on the Canon EOS R6 Mark II, and will work on cameras made after it – such as the R8, R50, R5 Mark II and R1.

That being said, the beta sample threw up an error message with my original EOS R5, so older cameras will likely need a firmware update to work properly with the lens (though my EOS R6 Mark II worked without a hitch).

This lens feels tailor-made for folks like myself currently shooting on older wide-angle EF lenses. My go-to wide-angle is currently the EF 16-35mm f/2.8L II USM, which I use on my R-series cameras with an adapter. It’s not an ideal setup, as it’s quite large with the adapter factored in, and being a lens from 2007 it lacks Optical IS and the clarity we've come to expect from more modern lenses, but it gets the job done.

I’ve recently been contemplating an upgrade and my options would be sticking with older non-stabilized DSLR EF glass, like the Canon EF 16-35mm f/2.8L III USM, or the newer Canon RF 15-35mm f/2.8L IS USM (there are, of course, slower f/4 iterations, too). Both of these are expensive options over the two grand mark, so this is a welcome more affordable option.

My only real complaint with modern RF lenses is that they use fly-by-wire manual focus rather than real-time. And while admittedly the autofocus is so good that the majority of the time I never need to manually focus, the times when I do need to quickly set it to a custom distance I prefer the more manual approach – and using the focus distance window found on my old EF glass.

My other reservation about using this lens, particularly with a view to using it for street photography, is that the zoom tops out at 28mm, just ever so slightly short of the very popular 35mm focal length for street shots. You could artificially crop in from 28mm to 35mm, using a camera like the R5 or R5 Mark II that both have bags of resolution to spare. I do think this will be a sticking point for those upgrading from a 16-35mm lens, as you’ll have to learn to get that bit closer or shoot wider.

So that’s the focus, what about the image quality? Well, some of the recent Canon wide-angle lenses have been subject to criticism with regard to their RAW files displaying heavy vignetting, distortion and optical imperfections. Canon wanted to set the record straight with this aspect of its lens design in recent models, such as this new optic and the Canon RF 10-20mm f4 L IS STM, which is where I first noticed this phenomenon.

Canon says wide-angle lenses like these have been made to produce heavy vignetting in the corners on purpose, with a smaller imaging circle, and have extra lens resolution factored in from the design stage, enabling the dark corners to be stretched out in post to remove the dark corners where the imaging circle doesn't cover the sensor.

It explained that designing the lens this way enables it to be lighter, smaller and less expensive than a more 'optically perfect' lens, and the company maintains that the image quality of the new Canon RF 16-28mm f/2.8 IS STM is comparable to the Canon EF 16-35mm f/2.8L III USM. My tests with the beta sample certainly point towards this being the case.

In my book there's nothing wrong with this approach – smaller, lighter and more affordable lenses are to be celebrated – just be aware that a lens profile is absolutely essential when working with its RAW files. Of course, if you only shoot JPEGs you won't even notice this design choice as it's corrected in-camera – and so is the Live View, so you never see the distracting dark corners when you're framing up your shots.

There’s something very interesting going on with the lens corrections on some of Canon’s wide-angle RF lenses, as both the unstretched RAWs and the stretched JPEGs give an identical resolution – so there has to be some sort of interpolation going on. This isn't necessarily at the cost of image quality, though, as Canon claims the lenses have been designed with extra optical resolution baked in to account for this – very clever!

During my hands-on I compared the new RF 16-28mm f/2.8 IS STM to my EF 16-35mm f/2.8L II USM. The RAW files show heavy vignetting without a lens profile, as expected, but even the corrected JPEGs that have a profile applied suffer from vignetting – although it's not the harsh black corners you see in the RAWs .

There is still vignetting once corrected as in the JPEGs, particularly at f/2.8, though it's pretty much gone by the time you close down to middle apertures like f/8. I guess this is the compromise you'll have to make, dealing with some vignetting to get a smaller, lighter and more affordable lens – there are worse imaging defects to contend with, and vignetting can usually be removed fairly easily in post.

Beta test shots at 16mm

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Putting the vignetting to one side, the 16-28mm surprisingly trumped my older EF 16-35mm f/2.8L II USM lens in pretty much every other aspect, it’s a little sharper and unlike my old DSLR optic it has much lower levels of chromatic aberration (also called fringing) where unsightly purple and green outlines can be seen in areas of high contrast – impressive!

Beta test shots at 28mm

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High-contrast areas did tend to have a very faint white outline to them and where they looked oversharpened, this was something I didn’t notice on its more premium RF 15-35mm f/2.8L brother. It’s a shame the lens didn’t want to play ball with my EOS R5, as I would have keen to zoom in on some 45MP files to really get a good gauge of the lens resolution and how it copes with ultra-fine details.

As expected, Canon’s RF 15-35mm f/2.8L IS USM delivered better image quality, but by less than you'd probably think. Okay, yes, the vignetting isn't great, though we’ll have to see how the production sample performs for our final verdict, but in terms of sharpness and clean images free from chromatic aberration it wasn’t bad at all.

Canon RF 16-28mm f/2.8 IS STM: Verdict

So should you buy the Canon RF 16-28mm f/2.8 IS STM? Well, it certainly adds another option if you're in the market for a Canon first-party wide-angle zoom – and it slots in nicely between the Canon RF 15-30mm f/4.5-6.3 IS STM and the Canon RF 14-35mm f/4L IS USM. In many ways the new release has cannibalized both of these lenses, as I can't see many reasons why you wouldn't choose it over them – it packs in so many features as well as decent image quality all in a travel-friendly package.

When it comes to wide-angle lenses with the same fast f/2.8 maximum aperture, it's slightly trickier to justify the purchase. Your options here are the Canon RF 15-35mm f/2.8L IS USM which is about twice the price, though if you're willing to go down the second-hand route it's actually not too dissimilar! So if you're in this boat you'll need to weigh up whether you want a safe and reliable, optically sound and more comprehensively weather-sealed L-series with a pre-loved Canon RF 15-35mm f/2.8L IS USM, or compromise on image quality a little with the Canon RF 16-28mm f/2.8 IS STM.

If you currently own a Canon EF 16-35mm f/2.8L USM III (or Mark II like myself) the choice is clear, this new 16-28mm impressively outputs similar if not sharper results in a compact and light package and is certainly more convenient than using the Canon EF-EOS R mount adapter, so it's a bit of a no brainer!

Alternatives

Canon RF 50mm f/1.8 IS STM – Canon's must-have prime is also its cheapest. It's nowhere near as advanced or optically impressive, but it's truly tiny and is also stabilized – helpful if you don't have a camera with IBIS.

Canon RF 50mm f/1.2L USM – The first ever L-series RF prime lens, the 50mm f/1.2 is huge, heavy and a low-light monster – but it's also a heck of a lot heavier, isn't stabilized, and is too chunky to be a go-to video lens.