Canon RF 24-240mm f/4-6.3 IS USM Review | The Best Full-Frame 10X Super-Zoom Ever!

Have you ever dreamed of having just one lens that covers an entire zoom range from, say, 24mm to 240mm? But, then you laugh because it sounds too good to be true, right? Just a few years ago, you would have been right. Almost all “superzoom” lenses were, simply put, terrible.

Especially with the constraints of a DSLR camera mount, the relatively deep flange distance necessary to accommodate a mirror flopping up and down, there were many 24-200mm or 28-200mm zoom lenses out there, mostly made by the likes of Sigma and Tamron, and they all had one thing in common: Their image quality was almost un-usable throughout one portion of their focal range or another, making them pointless to choose compared to a pair or trio of zooms with a lesser factor of zoom than 10X.

When Canon created their full-frame mirrorless system, the RF mount, they gave themselves virtually no constraints, which allowed them to create optics that were just not previously possible.

While many of those lenses are exotic, (f/1.2 primes, f/2 zooms, etc.) others are quite modest, indeed, aimed at beginners and those photographers who just want a simple, lightweight kit overall.

This is where the Canon RF 24-240mm f/4-6.3 IS USM comes into the picture. It’s a 10x superzoom, and as such, it is truly impressive. Pair it with a faster but still modest prime lens such as the Canon RF 50mm f/1.8 STM, on ca camera body like the Canon EOS RP, and you have quite possibly the lightest two-lens kit available for full-frame that covers such a wide focal range and aperture range.

So, how good is this Canon 24-240mm? Is it as incredibly sharp as the RF L zooms it equals, the Canon RF 24-70mm f/2.8 L IS and the Canon RF 70-200mm f/2.8 L IS? No, of course, it’s not perfect. Those are professional L-clas lenses, costing well over $2,000 each. This lens comes in at under $1,000 and is not “Canon L glass”.

SPOILER ALERT! Simply put, the RF 24-240mm isn’t perfect, of course, but it is good enough that it’s worth considering, especially if the thought of not having to change lenses nearly as often appeals to you, without having to sacrifice the high image quality you can get from a full-frame mirrorless camera.

Canon RF 24-240mm f/4-6.3 IS USM Specifications

Canon RF 24-240mm f/4-6.3 IS USM Review | Who Should Buy It?

Virtually all photographers love the idea of a 24-240mm lens. Whether you’re a portrait or wedding photographer, or a landscape or wildlife photographer, it’s always useful to be able to zoom from a decent wide-angle focal length to a longer focal length, without changing lenses!

However, there is a reason that these lenses aren’t extremely common/popular! There is a reason why even the best, professional, high-dollar zoom lenses are usually just 2-3X zooms.

First and foremost, a 10X zoom lens must make some compromises on sheer image quality. They can lack sharpness at one end of the zoom range, and/or be terribly soft in the corners at all focal lengths. They can also be plagued by troubles with other aspects of image quality, such as vignetting, distortion, and color fringing.

This might be okay for casual photography during the daytime, but it means that most superzoom or “kit” lenses will fail to perform well enough for things like low-light action, wildlife, or even just candids or journalism. Not to mention the creative limitation of not having apertures like f/2.8 or f/1.8 at your disposal, of course.

So, with that in mind, let’s talk about different types of photography where you might actually put a decently sharp, relatively slow-aperture 10X full-frame zoom lens to good use!

[Related Reading: Canon RF 600mm f/11 Lens Review | Crazy Long & Crazy Affordable]

Wedding Photography

Simply put, this lens is not a professional wedding photography lens. It might be the lens you reach for if your wedding is outdoors in broad daylight, AND if your more professional lenses break or get stolen or something horrible. This is not the lens you “invest in” for professional work as a wedding photographer.

Could you “get the job done” with this lens at a wedding? Sure, if you knew what you were doing, and if you were either working in broad daylight or had additional strobe/flashes available to illuminate any dark moments. Still, you would be in quite a predicament if you tried to use this lens around, say, 70-200mm to capture wedding reception toasts or the first dance in a dimly lit indoor venue.

Portrait Photography

This slow-aperture zoom lens could maybe be useful for portraits in the daytime, especially for things like active family portraits where your subjects, such as small children, are running away from the camera, or very close up to it, and you want to capture all sorts of candid moments without ever stopping to change lenses.

Walk-Around, Candid, & Street Photography

Action Sports & Wildlife Photography

You might not really need this much zoom range for either subject; usually, the more well-suited lenses for both action sports and wildlife photography are dedicated telephoto zooms, such as 70-300mm, 100-400mm, or even longer telephoto zoom lenses. Yes, they are much bigger, heavier, and yes, they are often just as “slow” with their aperture. However, they’re also going to provide much better “reach” for those distant subjects, and despite the similarly slow apertures, the actual lens focus speed itself will be quite fast.

Having said that, 240mm is certainly nothing to scoff at for many types of action sports and wildlife subjects. If you’re working under decently controlled conditions, and especially if it’s daylight, then 240mm worth of reach might be all you need.

Landscape, Cityscape, & Travel Photography

Obviously, photographers who spend all their time at f/11, as the stereotype goes, might strongly consider a slow-aperture zoom such as this. The only question you might need to ask is, how sharp is it? The answer is, as I already stated, quite good.

It’s not flawless, of course. The extreme corners aren’t as perfectly sharp as the center of the image, but at least you can use any focal length you want and only ever see faint softness in the extreme corners. (When stopping down, that is. More about the sharpness later.)

Whether you go on epic wilderness adventures, or you’re just a casual landscape or cityscape photographer, you’ll appreciate that this is, quite simply, the sharpest full-frame 10X zoom lens I have ever tested. Other full-frame camera systems aren’t going to offer this same level of image quality in a single lens unless you give up some of the zoom range. So, if you love to travel light but still bring a respectable one-lens full-frame kit on all your vacations, travels, and adventures, then this Canon has got you covered.

Nightscape & Astrophotography

You might think that since I so quickly dismissed this lens as a wedding or portrait lens due to its slow aperture, that it might be a terrible idea to try and use it for nightscape or astrophotography.

Honestly, though? Once you get your camera on a tripod, as you should for all Astro-landscape type work, the slower aperture is not that bad. At least, not at the wide end of the focal range, where you are most likely to use it for nightscape photography.

All in all, I’d say it is a good choice for the travel/landscape photographer who often also does a little bit of nightscape photography, maybe not on the most pitch-dark nights in remote locations, but certainly night cityscapes, or anywhere there is a bit of moonlight or any other ambient light to work by. Don’t underestimate this lens’s capability after the sun goes down!

Is it the best choice for telephoto photography at night, whether casual or serious deep-sky work? No, however, the sharpness of stars at all focal lengths is still quite impressive, the best I’ve ever seen for a 10X zoom.

Canon RF 24-240mm f/4-6.3 IS USM Review | Pros & Cons

This is an impressive lens, indeed, but it’s not without caveats. (Caveats being a nice word for notable flaws.) It is compact and lightweight compared to any two lenses that might cover its same range, of course, and it’s much more affordable than buying two comparably good, sharp lenses. In other words, the biggest PRO is, of course, it’s one lens that covers from 24mm to 240mm.

But, to achieve this package, Canon made a few compromises. Fortunately, they’re rather smart compromises, mostly buried “under the hood” so to speak, and you might not really notice them unless you look closely.

Image Quality

Sharpness is quite impressive throughout the entire zoom range, especially if you aren’t really picky about the extreme corners of your image frame. Actually, even wide-open, it is very sharp in most of the image frame!

As with many superzooms, and basically, any zoom lens that is a compromise that favors portability and affordability, it starts off being incredibly sharp at the wide end, and stays incredibly sharp throughout most of the mid-range, and only gets a bit soft at the very long telephoto end. Even then, in ideal conditions, it is actually quite decent at 240mm!

When you pick up a lens that has “f/4-6.3” on it, you don’t think that shallow depth of field, or super-smooth bokeh, is/are going to be something you can get excited about. Honestly? With most superzoom lenses, it’s the luck of the draw; the bokeh is what it is, take it or leave it!

[Related Reading: Canon RF 70-200mm f/2.8 L IS Review]

What you don’t realize is this: 240mm, even at f/6.3, is capable of some very shallow depth, especially the closer you focus. And, as is Canon’s forte; once you get shallow depth, whether with an “L” class lens or not, the bokeh is quite smooth.

Honestly, the best sample of bokeh that we were really happy with is the above stock/sample image from Canon. We weren’t able to test this lens when the cherry blossoms were blooming around here, so, there you go!

Colors & Contrast

Colors and contrast are beautiful. If you’re worried about “that special Canon look” not being present due to the fact that this isn’t L glass, I will say this: you’re more likely to see a color/contrast difference between a Canon sensor and a sensor from any other manufacturer. You’re also more likely to see a difference between any Canon lens, and any third-party lens, again in terms of color and contrast.

In other words, aside from the look of the bokeh and the slightly less-than-perfect sharpness, you’re getting almost the full Canon experience as far as the overall look of the images are concerned.

Vignetting & Distortion

This is where things get complicated. There is no free lunch when it comes to making a 10X zoom lens, and where Canon cut corners is mostly revealed in the vignetting and distortion of this lens.

It’s a good thing the profile works so well, too, because at 24mm, with correction turned off, there are totally black corners. That’s correct; you absolutely must turn on the vignetting correction to shoot at 24mm, at any aperture, unless you plan to crop all your photos to 4:5 or 16:9.

Speaking of problems that are only visible when you horribly over-edit your photos, there is one very important thing to watch out for if you ever get really heavy-handed with fine detail adjustments, such as sharpening, but also the Clarity and Texture sliders in Adobe Lightroom.

With the correction profile turned on for vignetting, you will get utterly catastrophic banding all over your image if you over-edit the fine detail in your image. Not to worry, though; if you edit your details the RIGHT way, you can avoid the problem.

Sunstars & Flare

There are flare dots, but not too many. Sunstars are present when stopping down to f/11-16, and are decent looking. These are the types of things where you just have to “roll with it”; if you want a lens with minimal flare and gorgeously pointy sunstars, you’ll probably want to get a more specialized lens instead of, or in addition to, this 24-240mm.

Color Fringing, Aberration, Coma & Astigmatism

Surprisingly, unlike the heavy vignetting and distortion that absolutely needs to be corrected, when it comes to chromatic aberrations, color fringing, and coma/astigmatism, the levels are all surprisingly low!

As with most all modern lenses, chromatic aberration is well-corrected by turning on the Adobe defaults for that, and coma/astigmatism are, well, not terrible, considering this is a heavily corrected superzoom.

Bottom line: would I photograph a moonlit nightscape with this lens? Yes. In fact, I’d expect it to deliver results that looked nearly identical to flagship L lenses, at resolutions suitable for social media, at least.

Is it sharp enough to stand up to the likes of the Canon RF L zoom lenses with a constant f/2.8 or even f/2 aperture, at higher megapixel resolutions? No, of course not. But it’s still impressive, for a 10x zoom that costs under $1K.

Macro & Close-Up Photography

As with most modern “kit” and superzoom lenses, you don’t have to worry about the lens “getting soft” when focusing really close, although the corners will likely begin to appear soft due to field curvature.

The actual closest focusing distance isn’t terrible, with a maximum magnification of 0.26x but it isn’t anything like the dedicated Canon RF macro lenses. (They’re actually 1:2, 0.5x)

Design & Durability

The Canon RF 24-240mm f/4-7.3 is very well-built; despite having some plastic parts, it feels like a very quality product that will stand the test of time. This is not your average kit lens that breaks after a year; in fact, I would expect it to last just as long as a Canon L lens, that is if you are able to take good care of it, year after year. It’s not weather-sealed, of course, but in my experience, even un-sealed lenses can still survive a light rain; it’s the severe dust that you have to watch out for.

Autofocus Performance

With whatever latest-and-greatest AF technology Canon is using, this lens definitely focuses amazingly well in most conditions. It’s snappy and fast, especially when working with closer subjects and at wider focal lengths.

The only time I felt like the lens itself was causing the camera AF system to “go hunting” was, of course, at the 240mm f/6.3 end of the zoom range, and when shooting in dimmer, darker conditions.

Features & Customization

Secondly, I am a little disappointed that Canon made the focus ring double as the control ring. It’s not a problem if you never got used to RF lenses and their control ring, or if you never use manual focus, but if you use both of those things a lot, flipping the Focus/Control switch back and forth all the time takes some getting used to.

For $900, and on a lens the size of the 24-240mm, I wish Canon had included a cheap plastic hood, and both a dedicated focus ring and command/control ring.

Canon RF 24-240mm f/4-6.3 IS USM Review | Compared To The Competition

As I just pointed out, the alternatives that are native to the Canon RF mount are all significantly more expensive. In most cases, you’ll have to buy two lenses to cover this much zoom range!

…but you’d be spending even more money, and wouldn’t be getting significantly better image quality besides the 240-300mm range which is actually pretty decent on the latest Canon 70-300mm.

Canon RF 24-240mm f/4-6.3 IS USM Review | Conclusion

Canon did the impossible: They made a very decent, even a darn-good 10x full-frame zoom lens. There is a reason you don’t see 16-160mm lenses, or 100-1000mm lenses: They are impossible unicorns, if you want sharp results in a portable package.

Canon’s 24-240mm f/4-6.3 is, in fact, a bit of a unicorn lens, despite its merely “good” image quality that is surrounded by stunningly sharp “L glass” that mostly costs well over $2,000. It’s not for everybody, of course, but if the conditions you work in are acceptable, and your creative style can accommodate the lens’s limitations, this is your best choice for a portable superzoom in the entire full-frame mirrorless realm.

Check Pricing & Availability

The Canon RF 24-240mm f/4.6.4 IS STM can be found for $899 on B&H, and the accessory hood can be found for $39.99, also on B&H.

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