Does a fun-to-use, lightweight, wide-aperture, close-focusing, affordable lens with an ultra-popular wide-angle focal length sound intriguing? This lens has these features, so read on. The Canon RF 24mm F1.8 Macro IS STM Lens might have your name on it.
Does it seem like you've seen this lens before? That feeling is not surprising as the Canon RF 24mm F1.8 Macro IS STM Lens shares a significant resemblance to the Canon RF 35mm F1.8 IS STM Macro Lens.
Aside from the focal length difference, these lenses share many commonalities.
The focal length (or the focal length range for a zoom lens) is the first attribute to consider for lens selection. Focal length drives subject distance choices, which determine perspective.
The 24mm focal length, just breaking into the ultra-wide class, is extremely popular.
Landscape photography is a perfect use for a 24mm lens. This focal length is quite wide and can allow an entire scene to remain in focus. Still, 24mm is not so wide that it complicates composition and not so wide that it makes distant details (such as mountains) tiny.
A solid percentage of my landscape images are captured at 24mm, and this focal length is optimal for nightscapes
Architectural photography, large product photography, interior photography, and birthday parties are just a few uses for 24mm. This is a convenient focal length to leave mounted on the camera, ready to document life.
Wedding and event photography often utilize a wide-angle lens for capturing the large scene, for environmental-type and group portraits, including in tight spaces.
Photojournalists' needs are often similar to those of a wedding photographer and regularly include 24mm, and videographers frequently find the 24mm focal length to be just right.
While telephoto lenses are more frequently used for sports, a 24mm angle of view provides a very different perspective at these events. This focal length can be used to capture the big picture of the venue, overhead shots of the athletes and their coaches being interviewed after the game, and, when access permits, full-body environmental action sports photos showing a large amount of venue in the background. Note that when used for action sports with a close and rapidly approaching subject, the subject rapidly changes size in the frame, making it challenging to capture the perfect pose at the perfect framing distance in the 24mm angle of view.
Here are two comparisons showing the 24mm angle of view as it fits into a larger range.
APS-C sensor format cameras utilize a smaller portion of the image circle, meaning a scene is framed more tightly, with 1.6x being the angle of view multiplier for Canon's lineup. This lens's APS-C angle of view (38.4mm full-frame equivalent) shifts the uses of this lens toward portraiture, product photography, and documentary use.
The f/1.8 in the name refers to the maximum aperture, the ratio of the focal length to the entrance pupil diameter, available in this lens. A lens's max aperture opening is a key consideration for lens choice.
The lower the aperture number, the wider the opening, and the more light the lens can deliver to the imaging sensor. Each "stop" in aperture change (full stop examples: f/1.4, f/2.0, f/2.8, f/4.0, f/5.6) increases or decreases the amount of light by a factor of 2x (a substantial amount). This lens's f/1.8 opening is 1/3-stop wider than f/2.
The additional light provided by wider aperture lenses permits sharp images of subjects in motion and with the camera handheld in lower light levels and with lower (less noisy) ISO settings. In addition, increasing the aperture opening provides a shallower DOF (Depth of Field) that creates a stronger, better subject-isolating background blur (at equivalent focal lengths). Often critical is the improved low light AF performance availed by a wide-aperture lens.
A narrow aperture's advantages are related to (often significantly) reduced lens element size, including smaller overall size, lighter weight, and lower cost. Everyone loves those attributes, and this lens has them.
Because the aperture is measured as a ratio of lens opening to focal length, the focal length must be considered when assessing how wide a lens's aperture can open. At 600mm, f/4 is a massive opening. In a 24mm lens, f/1.8 is moderately wide and surpassed only by the f/1.4 24mm prime lens options.
Wide apertures are not always needed, especially at ultra-wide-angle focal lengths.
Motion blur is caused by subject details crossing over imaging sensor pixels during the exposure. Although this lens can be used with a very close subject rendered large in the frame, lenses such as this one are often used at normal (or even long) subject distances. The low magnification means those subjects' details more readily stay in their pixels, enabling the longer exposures required to compensate for the narrower aperture to still deliver sharp results, free of subject or camera motion blur.
Many of the uses for this lens require a narrower aperture, such as f/8 or f/11, to keep everything in the frame sharp, and photographers concentrating on landscape, architecture, real estate, etc., may seldom use the f/1.8 option.
Still, the f/1.8 aperture is an extremely valuable feature of this lens. Those photographing moving subjects, such as at sports events or under the night sky where light levels are so low that the earth's rotation becomes a source of camera motion, will appreciate this lens's capabilities.
It is hard to diffusely blur the background with the low magnification provided by an ultra-wide-angle lens. Such lenses render the background details small, keeping the background subjects more recognizable (and potentially distracting). Still, this lens's extremely short minimum focus distance and wide aperture can make a strong blur happen, adding artistic advantages to this lens's list of highly-desired features.
These examples illustrate the maximum blur this lens can create at the respective aperture:
What advantage does f/1.8 provide over your widest 24mm lens's max aperture? Again, consider this lens's ultra-close minimum focus distance.
Only a 1/60 second shutter speed (twice the framerate) is needed for 30 fps video capture, and wide apertures are not often required to get 1/60 in normally encountered ambient lighting.
Making the RF 24mm f/1.8 an even better choice for many low light needs is image stabilization. While image stabilization is not useful for stopping subject motion, it is incredibly useful for stopping camera motion, and this feature greatly extends the versatility of this lens. A still image presented to the AF system also enables it to be more precise.
The Canon RF 24mm f/1.8 IS STM Macro Lens's IS system features an impressive CIPA 5-stops of assistance rating, and coordinated IS with a camera having IBIS allows for up to 6.5 stops of correction.
The RF 24mm f/1.8's IS system is extremely quiet, with a barely perceptible "hmmm" heard only with an ear close to the lens. Image stabilization provides a stabilized view to the electronic viewfinder, with no image jumping or drifting occurring. Stabilization remains smooth during panning, an especially useful attribute for video recording.
Notable is that, at review time, Canon has only one image stabilized lens with an aperture wider than this one and its 35mm sibling, the EF 85mm f/1.4L IS USM Lens.
The IS On/Off switch on the lens conveniently controls the lens and in-body image stabilization systems simultaneously.
When you need/want to leave the tripod behind, IS is there for you, helping to ensure sharp images and adding significant versatility to this lens. When vibrations, such as those caused by wind, are present when using a tripod, IS can save the day, enabling image capture not otherwise possible.
While getting the right focal length and maximum aperture opening are high priorities for lens selection, the image quality produced by a lens is another important selection aspect. A small, lightweight, affordable, consumer-grade lens is not expected to deliver the ultimate image quality, but the bar for this lens grade has been rising.
Let's start by looking at the sharpness aspect, a combination of resolution and contrast. At f/1.8, subject details in the center of the frame are quite sharp.
In general, lenses are not as sharp at their wide-open apertures as they are when stopped down one or two stops, and this generalization tends to be stronger for consumer-grade lenses. However, this lens is sharp enough at f/1.8 that only slight improvements are seen through f/2.8, where this lens produces excellent center-of-the-frame sharpness.
Often, subjects are not placed in the center of a composition. In the periphery of the image circle, where light rays are refracted to a stronger angle than in the center, lenses typically show decreased sharpness, and this one shows a gradual decline.
While extreme full frame corner image quality is poor at f/1.8, the periphery image quality is decent. Stopping down through f/4 produces peripheral sharpness improvements, especially clearing vignetting, and f/4 images have very good corner sharpness. Another bump in corner sharpness is seen at f/5.6.
Taking the testing outdoors, we next look at a series of center-of-the-frame 100% resolution crop examples. These images were captured using an ultra-high resolution Canon EOS R5 with RAW files processed in Canon's Digital Photo Professional (DPP) using the Standard Picture Style with sharpness set to 1 on a 0-10 scale. Note that images from most cameras require some level of sharpening, but too-high sharpness settings are destructive to image details and hide the deficiencies of a lens.
Be sure to find details in the plane of sharp focus for your evaluations. As mentioned, this lens is sharp in the center at f/1.8.
Next, we'll look at a series of comparisons showing 100% resolution extreme top left corner crops captured and processed identically to the above center-of-the-frame images. The lens was manually focused in the corner of the frame to capture these images.
Samples taken from the outer extreme of the image circle, full-frame corners, can be counted on to show a lens's weakest performance, and this lens's f/1.8 corner performance is poor. Stopping down to f/5.6 brings noticeable corner improvements, though still more would be welcomed.
Does corner sharpness matter? Sometimes it does, sometimes it doesn't. Landscape and architecture photography are two photographic disciplines that have frequent scenarios requiring sharp corners. However, those scenarios usually require apertures narrower than f/4.
When shooting at the widest apertures, depth of field is often shallow, and the plane of sharp focus less frequently includes details showing in a corner, making corner sharpness less important. I always prefer my lenses to be razor sharp in the corners in case that feature is needed, but each of us must consider our applications to answer this paragraph's initial question, and if no better option is obtainable, any limitations present must be accepted.
This lens does not exhibit focus shift, the plane of sharp focus moving forward or backward as the aperture is narrowed (residual spherical aberration or RSA).
A lens can be expected to create peripheral shading at the widest aperture settings when used on a camera that utilizes a lens's entire image circle. Wide-angle, wide aperture lenses tend to show strong peripheral shading wide open, and the about 4 stops of shading in this lens's corners is very strong.
Reducing shading usually requires selecting a narrower aperture. At f/2.8, just over 3 stops of corner shading remains, and at f/4, about a stop and a half shows. Slight decrease is seen in apertures narrower than f/4.
APS-C format cameras using lenses projecting a full-frame-sized image circle avoid most vignetting problems. In this case, the about 1.5 stops of corner shading showing at f/1.8 may be visible in select images, primarily those with a solid color (such as a blue sky) in the corners.
One-stop of shading is often used as the visibility number, though subject details provide a widely varying amount of vignetting discernibility. Vignetting is correctable during post-processing, with increased noise in the brightened areas being the penalty, or it can be embraced, using the effect to draw the viewer's eye to the center of the frame. Study the pattern shown in our vignetting test tool to determine how your images will be affected.
Lateral (or transverse) CA (Chromatic Aberration) refers to the unequal magnification of all colors in the spectrum. Lateral CA shows as color fringing along lines of strong contrast running tangential (meridional, right angles to radii) with the mid and especially the periphery of the image circle showing the most significant amount as this is where the most significant difference in the magnification of wavelengths typically exists.
With the right lens profile and software, lateral CA is often easily correctable (often in the camera) by radially shifting the colors to coincide. However, it is always better to avoid this aberration in the first place.
Color misalignment can be seen in the site's image quality tool, but let's also look at a worst-case example. The image below is a 100% crop from the extreme top left corner of a Canon R5 frame showing diagonal black and white lines.
Only black and white colors should appear in these images, with the additional colors indicating a modest presence of lateral CA.
A relatively common lens aberration is axial (longitudinal, bokeh) CA, which causes non-coinciding focal planes of the various wavelengths of light. More simply, different colors of light are focused to different depths. Spherical aberration along with spherochromatism, or a change in the amount of spherical aberration with respect to color (looks quite similar to axial chromatic aberration but is hazier) are other common lens aberrations to observe. Axial CA remains somewhat persistent when stopping down, with the color misalignment effect increasing with defocusing. The spherical aberration color halo shows little size change as the lens is defocused, and stopping down one to two stops generally removes this aberration.
In the real world, lens defects do not exist in isolation, with spherical aberration and spherochromatism generally found, at least to some degree, along with axial CA. These combine to create a less sharp, hazy-appearing image quality at the widest apertures.
The example below looks at the defocused specular highlights' fringing colors in the foreground vs. the background. The lens has introduced any fringing color differences from the neutrally-colored subjects.
Strong color separation at f/1.8 rapidly diminishes by f/4.
Bright light reflecting off lens elements' surfaces may cause flare and ghosting, resulting in reduced contrast and sometimes interesting, usually destructive visual artifacts. The shape, intensity, and position of the flare effects in an image are variable, dependent on the position and nature of the light source (or sources), selected aperture, shape of the aperture blades, and quantity and quality of the lens elements and their coatings. Additionally, flare and ghosting can impact AF performance.
This lens features Canon SSC (Super Spectra Coating) to prevent flare and ghosting. Additionally, a low 11-element count is helpful in this regard. This lens produced only few flare effects in our standard sun in the corner of the frame flare test at f/1.8, but at narrow apertures, flare effects become moderately strong.
Flare effects can be embraced or avoided, or removal can be attempted. Removal is sometimes very challenging, and in some cases, flare effects can be quite destructive to image quality.
Two lens aberrations are particularly evident in images of stars, mainly because bright points of light against a dark background make them easier to see. Coma occurs when light rays from a point of light spread out from that point instead of being refocused as a point on the sensor. Coma is absent in the center of the frame, gets worse toward the edges/corners, and generally appears as a comet-like or triangular tail of light which can be oriented either away from the center of the frame (external coma) or toward the center of the frame (internal coma). Coma clears as the aperture is narrowed. Astigmatism is seen as points of light spreading into a line, either sagittal (radiating from the center of the image) or meridional (tangential, perpendicular to sagittal). This aberration can produce stars appearing to have wings. Remember that Lateral CA is another aberration apparent in the corners.
The image below is a 100% crop taken from the top-left corner of an R5 image captured at f/1.8.
Unless you like the creative star shapes shown above, you might consider clone stamping stars from the center of the frame over those in the periphery when using this lens.
To keep your opinion unbiased, an important image quality aspect of this lens was withheld until this point in the review.
The Canon RF 24mm F1.8 Macro IS STM Lens has significant barrel distortion. With increasing frequency, manufacturers are relying on software over physical lens design to handle geometric distortion.
With this lens, Canon opted to force correction of the severe barrel distortion in camera and in DPP, regardless of the lens corrections settings. This lens's distortion test results were processed outside of our standard to avoid the correction.
For reference, the squares in the test chart filled the viewfinder during capture. There is a lot of area outside of the framed composition in the RAW image.
Distortion correction is destructive at the pixel level as some portion of the image must be stretched (or the overall dimensions reduced), and this lens's images need a lot of stretching. That said, combine this information with the image quality shared to this point in the review. The correction most strongly affects the corner image quality.
As seen earlier in the review, it is easy to illustrate the strongest blur a lens can create, and wide-angle lenses are inherently disadvantaged in this regard. Due to the infinite number of variables present among all available scenes, assessing the bokeh quality is considerably more challenging. Here are some f/11 (for diaphragm blade interaction) examples.
The first example shows a 100% crop with defocused highlights filled rather smoothly and having rather round shapes relative to the amount the lens was stopped down.
The second set of examples shows full images that are reduced in size and look normal.
Except for a small number of specialty lenses, the wide aperture bokeh in the frame's corner does not produce round defocused highlights, with these effects taking on a cat's eye shape due to a form of mechanical vignetting. If you look through a tube at an angle, similar to the light reaching the frame's corner, the shape is not round. That is the shape we're looking at here.
The corner shapes are strongly out of round, but as the aperture narrows, the entrance pupil size is reduced, and the mechanical vignetting absolves with the corner shapes becoming round.
A 9-blade count diaphragm will create 18-point sunstars (diffraction spikes) from point light sources captured with a narrow aperture. Generally, the more a lens diaphragm is stopped down, the larger and better-shaped the sunstars tend to be. Wide aperture lenses tend to have an advantage in this regard, and this lens can produce beautiful stars, as illustrated below.
The example above was captured at f/16.
The optical design includes an aspheric element and an Ultra-low Dispersion (UD) glass element.
From an image quality perspective, the Canon RF 24mm F1.8 Macro IS STM Lens is a good performer for its price. The strong barrel distortion is the biggest issue, with corner image quality impacted the most. Peripheral shading is also strong at wide apertures.
Don't forget that APS-C format cameras utilize only the optimal central portion of the image circle.
Accurate focus is critical for most images, and most of us rely on autofocus for that task. Canon's EOS R-series cameras have been outstanding performers in this regard, accurately focusing with everything I mount on them. The RF 24mm f/1.8 IS STM Macro Lens is not an exception.
Driven by a leadscrew-type stepping motor (referenced by the "STM" in the moniker), this lens autofocuses with moderate speed. Short focus distance adjustments are quick, but long distance changes reveal the intermediate speed of this lens's AF system.
As a rule, wide aperture lenses enable AF systems to perform their best in low-light environments. This lens mounted on an EOS R5 impressively autofocuses on adequate contrast in extremely low-light scenarios, conditions considerably darker than I can see to navigate in. As usual, AF slows in low light.
From an audibility standpoint, this lens's AF system is not loud, but an audible buzz and some light clunking are heard, especially during long focus distance adjustments.
This lens has a front-focusing design, with the inner barrel extending up to 0.53" (13.4mm) at the minimum focus distance. This design, along with the forward positioning of the diaphragm, permits a lighter focus group and provides a very short minimum focus distance.
Canon's STM AF systems focus smoothly, a highly desired trait for movie recording. Also note that this lens's aperture adjusts quietly and smoothly, ideally-suited for video recording under changing lighting conditions.
FTM (Full Time Manual) focusing is supported in AF mode with the camera in One Shot Drive Mode, but the shutter release must be half-pressed for the focus ring to become active. Note that FTM does not work if electronic manual focusing after One Shot AF is disabled in the camera's menu. The lens must be in "MF" mode, and the camera meter must be on/awake for conventional manual focusing to be available.
I'm pleased that Canon gave this lens an AF/MF switch, a frequently used feature that is missing on many current lens designs.
The RF 24mm f/1.8's plastic-ribbed focus ring is modest in size, small enough that I sometimes grasp the control ring when attempting to manually focus (especially an issue when with gloves).
Approximately 170° of rotation imparts a full extent focus distance change at a nice rate. Turn the ring fast, and a longer rotation is required, apparently due to skipped adjustment readings.
While the focus ring turns smoothly, the focus adjustment occurs in annoyingly large steps, large enough to not always provide the precise focus distance required, especially when working with close-up subjects. Also, the composition shifts slightly when the focus ring rotation direction is reversed. This focus ring is lightly damped.
Normal is for the scene to change size in the frame (sometimes significantly) as the focus is pulled from one extent to the other. This is focus breathing, a change in focal length resulting from a change in focus distance. Focus breathing impacts photographers intending to use focus stacking techniques, videographers pulling focus, and anyone critically framing while adjusting focus. This lens produces a huge change in subject size through a full extent focus distance adjustment, but the macro focusing capability must be considered in this evaluation.
With a minimum focus distance of only 5.51" (140mm), this lens has a huge 0.50x maximum magnification spec. The half-life size 1:2 reproduction ratio is enough to garner the "Macro" designation in the product name.
|Canon RF 16mm F2.8 STM Lens||5.1"||(130mm)||0.26x|
|Canon RF 24mm F1.8 Macro IS STM Lens||5.5"||(140mm)||0.50x|
|Canon RF 35mm F1.8 IS STM Macro Lens||6.7"||(170mm)||0.50x|
|Canon RF 50mm F1.8 STM Lens||11.8"||(300mm)||0.25x|
|Canon RF 85mm F2 Macro IS STM Lens||13.8"||(350mm)||0.50x|
A subject measuring approximately 2.7 x 1.8" (69 x 46mm) fills a full-frame imaging sensor at this lens's minimum focus distance.
The image quality at minimum focus distance is good, with sharp details through much of the frame. The corners are an exception, but a narrow aperture makes even appear decent.
The USPS love stamps shared above have an image area that measures 1.05 x 0.77" (26.67 x 19.558mm), and the overall individual stamp size is 1.19 x 0.91" (30.226 x 23.114mm).
The minimum focus distance is measured from the imaging sensor plane with the balance of the camera, extended lens, and lens hood length taking their space out of the number to create the working distance. In this case, the plane of sharp focus is only about 1.4" (36mm) in front of the lens without the hood. Removing the hood adds some space, but the lens is still likely to impact subject lighting.
The Canon EF-S 35mm f/2.8 Macro IS STM Lens featured a built-in ring light, and it seems this lens could have incorporated the same. The RF 24mm f/1.8 does not feature grooves to mount Canon's macro flashes natively.
Need a shorter minimum focus distance and higher magnification? Mount an extension tube behind this lens to decrease and increase those respective numbers significantly. Extension tubes are hollow lens barrels that shift a lens farther from the camera, allowing shorter focusing distances at the expense of long-distance focusing. Electronic connections in extension tubes permit the lens and camera to communicate and function normally.
That said, it is unlikely that all except the shortest extension tubes would function with this lens.
As of review time, Canon does not offer RF mount-compatible extension tubes, but third-party options are available.
This lens is not compatible with Canon extenders.
Especially for a lens priced and featured as an affordable consumer lens, the Canon RF 24mm F1.8 Macro IS STM Lens seems nicely constructed with tight tolerances achieved.
Typical of lenses with front-focusing lens designs is extension during focusing, with this lens reaching its maximum 0.53" (13.4mm) extension at the minimum focus distance. The extended inner barrel has modest flex.
Enable the "Retract lens on power off" setting in the camera menu to ensure that the lens is fully retracted after use. However, know that the lens will not retain its focus distance if the camera goes to sleep with that setting enabled. With the setting disabled, powering off and on the camera initiates a focus retract and extend, but the focus distance remains the same.
With the camera on or off, the lens can be manually retracted by pushing the extended barrel into the lens, though I'm not sure Canon blesses this technique. Pressing the retracted inner barrel further into the lens while the camera is powered on results in a bad sound as the camera continuously attempts to push the barrel back out.
Utilizing engineering plastic construction, the slightly-textured exterior barrel looks and feels nice, as does the straight exterior diameter of this design. The manual focus ring has a slightly-grippy ribbed surface, with the control ring being strongly knurled for a tactile difference.
The control ring is configurable for fast access to camera settings, including aperture, ISO, and exposure compensation. Note that the control ring is clicked by default (54 clicks per revolution), and this ring's clicks are going to be audible in camera-based audio recordings. Canon offers a click stop removal service (at a cost).
The AF/MF and IS switches are flush-mounted with just enough raised surface area to be easily used, even with gloves. These 2-position switches snap crisply into position. Interesting is that opening and closing the memory card door opens the lens aperture momentarily and retracts, then extends the lens, even when the camera is powered off (changing the AF/MF switch position also did this on similar prior lenses).
This lens is not weather sealed, and the front and rear elements are not fluorine-coated to repel dust and water drops and to facilitate cleaning.
This compact, lightweight lens will take up little space in your bag and require little effort to carry all day.
|Model||Weight oz(g)||Dimensions w/o Hood "(mm)||Filter||Year|
|Canon RF 16mm F2.8 STM Lens||5.8||(165)||2.7 x 1.6||(69.2 x 40.1)||43||2021|
|Canon RF 24mm F1.8 Macro IS STM Lens||9.5||(270)||2.9 x 2.5||(74.4 x 63.1)||52||2022|
|Canon RF 35mm F1.8 IS STM Macro Lens||10.8||(305)||2.9 x 2.5||(74.4 x 62.8)||52||2018|
|Canon RF 50mm F1.8 STM Lens||5.6||(160)||2.7 x 1.6||(69.2 x 40.5)||43||2020|
|Canon RF 85mm F2 Macro IS STM Lens||17.6||(500)||3.1 x 3.6||(78 x 90.5)||67||2020|
For many more comparisons, review the complete Canon RF 24mm F1.8 Macro IS STM Lens Specifications using the site's lens specifications tool.
Here is a visual comparison:
Positioned above from left to right are the following lenses:
Canon RF 24mm F1.8 Macro IS STM Lens
Canon RF 35mm F1.8 IS STM Macro Lens
Canon RF 50mm F1.8 STM Lens
Use the site's product image comparison tool to visually compare the Canon RF 24mm F1.8 Macro IS STM Lens to other lenses.
The RF 24mm F1.8 features 52mm filter threads. These small filters are affordable and relatively popular.
As usual for Canon consumer lenses, the Canon RF 24mm F1.8 Macro IS STM Lens's EW-65B hood is optional — and not available at review time. This is a relatively shallow, plastic, petal-shaped hood with a release button facilitating easy installation and removal.
Also excluded from the RF 24mm f/1.8 lens box is a case. Canon suggests the Lens Case LP1016, a drawstring pouch that adds dust and minor impact protection (the bottom is well-padded). Consider a Lowepro Lens Case or Think Tank Photo Lens Case Duo for a quality, affordable single-lens storage, transport, and carry solution.
The relatively inexpensive consumer-grade RF 24mm Macro IS STM Lens is designed to be a high-value lens. This lens provides good utility and lots of fun for a low price.
As an "RF" lens, the Canon RF 24mm F1.8 Macro IS STM Lens is compatible with all Canon EOS R-series cameras, including full-frame and APS-C models. Canon USA provides a 1-year limited warranty.
The reviewed Canon RF 24mm F1.8 Macro IS STM Lens was online-retail sourced.
At review time, there are no close alternatives to the Canon RF 24mm F1.8 Macro IS STM Lens.
The closest sibling to compare is the Canon RF 35mm F1.8 IS STM Macro Lens. These lenses differ primarily by their focal length.
The image quality comparison shows the two lenses are nearly identical. Stopped down, the 35mm lens shows better corner performance. The 35mm lens has modestly less peripheral shading, fewer flare effects, and dramatically less geometric distortion. The 35mm lens shows some focus shift to the rear as the aperture is narrowed.
The Canon RF 24mm F1.8 Macro IS STM Lens vs. Canon RF 35mm F1.8 IS STM Macro Lens comparison shows the two lenses being nearly identical. The 35mm lens is $100.00 less expensive. The focal length difference is significant, but if that difference is not important to you, go for the 35mm lens.
Use the site's tools to create additional comparisons.
Throw the Canon RF 24mm F1.8 Macro IS STM Lens in the bag and carry it all day without burden. While little effort is needed to take this lens along, the utility it provides is quite high.
The 24mm focal length is frequently needed, the close-focusing capability adds many subjects and compositions, and the image stabilization improves realization of the good image quality this lens can produce when the tripod is left behind. The low price wraps up a great little package with a high fun factor.
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