Canon RF 24-240mm f/4-6.3 IS USM Review
The RF 24-240mm f/4L IS USM is a versatile, compact and lightweight 10x zoom lens for the Canon EOS R full-frame mirrorless camera system.
Featuring a Nano Ultrasonic Motor for smooth, precise and quiet continuous auto-focusing, Super Spectra coatings, 7 rounded diaphragm blades for smoother bokeh, a zoom lock switch to prevent lens creep, a switchable Focus/Control Ring, and image stabilisation offering a claimed 5-stop advantage, the Canon RF 24-240 lens is certainly a versatile all-rounder.
The Canon RF 24-240mm f/4-6.3 IS USM lens is priced at £899.99 / €1059.99 / $899.99 in the UK, Europe and the USA respectively.
Ease of Use
The Canon RF 24-240mm f/4-6.3 IS USM is amazingly small and compact considering the extremely versatile focal range that it covers, weighing in at just 750g and measuring 12.2cm in length, although it does extend to 19.5cm when the lens is set to 240mm.
Build quality is very good for what is after all a non L-series lens. The Canon RF 24-240mm f/4-6.3 IS USM feels solid enough in your hand, even if it is mostly made out of plastic.
The focusing ring is just about wide enough to quickly locate and it has a diamond knurled grip band for easier operation.
If you're not using the focusing ring for manual focusing, you can change its operation to be the Lens Control Ring instead via the dedicated Focus/Control switch on the side of the lens barrel.
In this setting, the ring which can be used to control certain key camera settings instead of the focusing. Although not a new idea in the wider photography world, this is one of the first times that Canon have incorporated this idea into their interchangeable lenses.
The Canon RF 24-240mm f/4-6.3 IS USM boasts Image Stabilisation which Canon claims offers an advantage of up to 5 f-stops over lenses without a stabilizer. This is activated via the Stabilizer On/Off switch on the side of the lens.
If the camera body supports it, Canon's IS technology is also able to detect intentional panning movement and automatically switch from the Normal IS mode to the Panning IS mode.
The Lock function switch is a useful feature that helps protect the lens. Set the focal length to 24mm and move it to the Lock position to prevent the zoom mechanism from creeping when the camera is pointed down or in storage.
The Canon RF 24-240mm f/4-6.3 IS USM lens has a focus ring with no hard stops at both ends of the range, making it more difficult to set focus at infinity.
It offers 100° rotation for more precise control over focusing. Polariser users should be pleased that the 72mm filter thread doesn't rotate on focus.
When it comes to auto-focusing, the Canon RF 24-240mm f/4-6.3 IS USM zoom is a speedy performer, taking under 0.20 seconds to lock onto the subject when mounted on the Canon EOS RP camera that we tested it with.
We didn't experience very much "hunting" at all, either in good or bad light, with the lens accurately focusing virtually all of the time. It's also a very quiet performer, thanks to the built-in Nano USM (Ultra Sonic Motor), which makes this lens well-suited to video recording.
There is a petal shaped lens hood (EW-78F) and a soft case (LP1219) for this lens, but disappointingly both are optional extras that aren't included in the box.
At the 24mm focal length the angle of view is 74°.
At the 240mm focal length the angle of view is 8°35'.
Chromatic aberrations, typically seen as purple or blue fringes along contrasty edges, are very well controlled with this lens - the example below shows the worst-case scenario.
With the lens wide open, 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/8 or smaller.
Barrel distortion is evident at the 24mm wide-angle focal length, but it disappears completely by 35mm.
The Canon RF 24-240mm f/4-6.3 IS USM is not a macro lens. The close-focus point is at 50cm from the film/sensor plane, and Canon quotes a maximum reproduction ratio of 0.26x for the lens when set to 240mm. The following example illustrate how close you can get to the subject.
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.
Canon have employed an iris diaphragm with seven rounded blades on the RF 24-240mm f/4-6.3 IS USM for a 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 this lens is, we are providing 100% crops on the following pages.