The Canon RF 28mm F2.8 STM Lens takes the highly desirable compact, lightweight, and affordable concepts to the extreme.
This full-frame lens weighs a mere 4.2 oz (120g). Out of 539 lenses in the site's database, only one lens, the Canon EF-M 22mm f/2 STM, at 3.5 oz (100g), weighs less. And, that lens only covers the APS-C format image circle.
Let's rave about the size next. The Canon RF 28mm F2.8 STM Lens, at 2.7" wide by 1.0" long (69.2 x 24.7mm), is the 4th shortest lens in the database. Two of the shorter lenses are APS-C models, and the third is the Canon EF 40mm f/2.8 STM Lens, measuring shorter by only a slight 0.07" (1.9mm).
What I said in that pancake lens review applies to this pancake lens: The diminutive Canon RF 28mm F2.8 STM Lens will inspire a high-pitched talking-to-a-baby voice from first-time viewers, with short drawn-out words and phrases such as "awwww" and "it's sooooo cuuute" being especially appropriate. It was even suggested that this lens could be used as a camera body cap.
Is affordability important to you? At review time, the 28mm F2.8 STM is the third least expensive Canon RF lens, with a list price equal to that of the Canon RF 24-50mm F4.5-6.3 IS STM Lens.
While inexpensive and effortless to take with you, the RF 28mm F2.8 STM Lens delivers impressive image quality — and it has great utility. The 28mm focal length is useful, including for vlogging, and the f/2.8 aperture is relatively wide, ready for low-light work.
Expect the Canon RF 28mm F2.8 STM Lens to be a best-selling lens.
Focal length (or the focal length range for a zoom lens) is the first consideration for lens selection. Focal length drives subject distance choices (or meets distance-related requirements), and subject distances determine perspective. Thus, you should be asking, what are the uses for a 28mm lens?
While not as common as 24mm and 35mm lenses, the 28mm focal length fills the gap between those angle of view needs.
This focal length has great general-purpose utility, including for around-the-house needs. This is a convenient focal length to leave mounted on the camera, ready to document life.
Landscape photography is a perfect use for a 28mm lens. This focal length is relatively wide and can allow an entire scene to remain in focus. Still, 28mm is not so wide that it complicates composition and not so wide that it makes distant details (such as mountains) tiny.
This focal length is good for nightscapes, especially for filling the frame with the width of the Milky Way.
Birthday parties, architectural photography, large product photography, and interior photography are more examples of 28mm uses.
Wedding and event photography often utilize a wide-angle lens for capturing the large scene, for environmental-type portraits, and for group portraits, including in tight spaces. Even groups of your largest subjects will fit in the frame.
Photojournalists' needs are often like those of a wedding photographer and often include 28mm. Videographers frequently find the 28mm focal length to be just right for their needs. This angle of view is a good choice for vlogging.
While telephoto lenses are more frequently used for sports, a 28mm angle of view allows 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 during after-the-game interviews, 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 28mm angle of view.
Here are two zoom-lens-captured comparisons showing the 28mm angle of view as it fits into a larger range.
APS-C sensor format cameras utilize a smaller portion of the image circle, and that means a scene is framed more tightly, with 1.6x being the angle of view multiplier for Canon's line-up. The 44.8mm full-frame angle of view realized on APS-C cameras shifts the uses of this lens toward portraiture, documentary, and product photography uses.
How much light does the lens provide to the imaging sensor? Usually, that question is the second most important when selecting a lens.
The f/2.8 in the name refers to the maximum aperture, the ratio of the focal length to the entrance pupil diameter, available in this lens.
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/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).
While few wide-angle prime lenses have max apertures narrower than f/2.8, this opening is still rather wide — wider than most consumer-grade zoom lenses.
The additional light provided by wider aperture lenses permits sharp images of subjects in motion, 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, attributes defining this lens.
These examples illustrate the maximum blur this lens can create at the respective aperture:
Here is another example illustrating the maximum blur this lens can create:
The 28mm angle of view is relatively wide, but this lens can still create a strongly blurred background.
The Canon RF 28mm F2.8 STM Lens does not feature image stabilization. Omitting the optical stabilization system reduces size, weight, complexity, and cost.
If stabilizing this lens is imperative, select a camera that features IBIS.
One aspect we never want compromised is the image quality produced by a lens. Still, this lens's low cost, light weight, and small size attributes are in opposition with great image quality. I was anxious to learn how the Canon RF 28mm F2.8 STM Lens performs optically.
Initially, we had the MTF charts and a predecessor lens to help us set expectations.
I happened to have the professional grade Canon RF 100mm F2.8 L Macro IS USM Lens MTF chart handy (it was included on the Canon RF 100-300mm F2.8 L IS USM Lens page). Let's look at this f/2.8 lens comparison.
The black lines indicate contrast, and the blue lines show resolution. The solid lines are sagittal, and the dashed lines are meridional. The higher, the better.
Photographers having experience with Canon's previous pancake lenses are not surprised to see this cheap little lens competing at this image quality level. The RF 28 is softer in the corners, but otherwise, it competes strongly and even shows an advantage at points in the radius.
With the RF 28 in hand, we see the impressive expectations become reality. This lens produces very sharp results across an entire full-frame imaging sensor at f/2.8. A slight increase in sharpness (contrast and resolution), is barely perceptible at f/4.
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. While this lens's extreme full-frame corners (with distortion corrected, the only option available in Canon Digital Photo Pro) are slightly softer than the center of the frame, they look excellent from a comparative standpoint.
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. The f/2.8 examples appear excellent, and the f/4 results are slightly sharper.
Samples taken from the outer extreme of the image circle, full-frame corners, show a lens's weakest performance, so 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.
These results look excellent at f/2.8 and outstanding by f/5.6.
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 is expected to show peripheral shading at the widest aperture settings when used on a camera that utilizes its entire image circle, and the just-under 3-stops of shading (with distortion corrected) in the RF 28's corners at f/2.8 will be noticeable.
Want less corner shading? Stopping down is the near-universal solution. Stop down one stop to reduce the corner shading by one stop. Further reductions are minimal, with about 1.5 stops of shading still present at f/16.
APS-C format cameras using lenses projecting a full-frame-sized image circle avoid most vignetting problems. In this case, the one-stop of corner shading showing at f/2.8 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 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 an EOS R5 frame showing diagonal black and white lines.
The color separation shown here is minor.
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 examples below look 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.
Color separation is showing in the f/2.8 results, but the amount is not strong.
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 and ghosting 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.
To avoid flare and ghosting, this lens features Canon SSC (Super Spectra Coating), and the low 8-element count is helpful in this regard. This lens produced only modest flare effects at narrow apertures in our standard sun in the corner of the frame flare test, reflecting excellent performance.
Flare effects can be embraced or avoided, or removal can be attempted. Unfortunately, removal is sometimes very challenging, and in some cases, flare effects can destroy image quality. Thus, high flare resistance is a welcomed trait of this lens.
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 that can be oriented either away from the center of the frame (external coma) or toward the center of the frame (internal coma). The 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 EOS R5 image captured at f/2.8.
The stars are showing signs of stretching in this sample, but the amount of stretching is minimal, and the shapes are good compared to most lenses.
As alluded to, this lens has extreme barrel distortion. The geometric distortion is so strong that Canon forces the correction in camera (EVF, LCD, JPG images, movies) and in DPP, regardless of the lens corrections settings. Processing this lens's images with third-party software reveals the true image captured.
The distortion test image shows the off-the-chart framing. For reference, the squares in the test chart filled the viewfinder during capture.
Stretching the image out to the as-framed composition requires AI. Although today's distortion correction AI is very good, AI does not know what the original subject details were in the stretched areas, and therefore, distortion correction is destructive at the pixel level.
Every lens is a compromise, with size, weight, price, image quality, and focal length range being common factors, and with increasing frequency, manufacturers are relying on software over physical lens design to manage geometric distortion. While severe distortion is a detriment to this lens, the offsetting factors are welcomed. Still, the distortion amount must be considered when comparing lenses, and an image captured from a non-distorted lens can be similarly up sized to even higher resolution using the same AI, potentially giving it an advantage.
Remember that APS-C format cameras utilize only the optimal central portion of the image circle.
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 available scenes, assessing the bokeh quality is considerably more challenging. Here are some f/11 (for diaphragm blade interaction) examples.
The first example shows smoothly filled defocused highlights, with the 7 aperture blades turning the circle into a heptagon shape when narrowed. The next two examples are 100% crops, and the last example is a full image reduced in size. Overall, the blur quality appears 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 shape truncation at f/2.8 is not strong. As the aperture narrows, the entrance pupil size is reduced, and the mechanical vignetting diminishes, making the corner shapes rounder.
A 7-blade count diaphragm creates 14-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 and wide aperture lenses tend to be advantaged in this regard. While the RF 28 produces strong spikes, the spikes are not pointy.
The design of this lens, illustrated below, should catch your attention.
The rear lens element, shown at the bottom of the diagram, is flat, protective glass. The next three wavy green elements behind the thin protective filter are aspherical elements.
"Aspherics go a long way toward the combination of wide-angle coverage and super compactness." [Rudy Winston, Canon USA]
Except for the strong barrel distortion, the Canon RF 28mm F2.8 STM Lens produces outstanding image quality.
With AF driven by a leadscrew-type stepping motor (referenced by the "STM" in the moniker), this lens autofocuses with reasonable speed. Short distance changes occur fast, but long focus distance changes show that this motor is not Canon's fastest.
While only clicks are audible during short focus adjustments, an easily audible buzz emphasizes the slightly slower speed during long-distance adjustments. Expect this AF sound to be recorded by the camera's mics (and your subject's ears).
This lens features a focus-extending design. When the camera is powered off, the RF 28mm F2.8 STM retracts to a parked position, with the inner barrel flush with the outer barrel.
Powered on, the lens extends slightly (1 or 2mm) when focused to infinity and extends slightly, approximately 7mm, at its minimum focus distance.
Rudy Winston, Canon USA, shares:
"The entire optical system (except for the rear-most, flat protective clear lens element) moves forward and backward as one unit, for focus control. There is no separate movement of some groups of optics vs. others, as we might see in a "floating" lens design. The lens barrel moves forward and backward to accommodate this focus movement; you can see the front section of the barrel seem to move forward and backward, during focusing – but it's not a major amount of shifting from nearest to infinity focus."
Generally, wide-aperture lenses enable AF systems to perform their best in low-light environments, and this lens focuses on adequate contrast in a very dark environment. As always, AF slows in low-light conditions.
Canon's STM AF systems' smooth focusing is a desired trait for movie recording.
The RF 28 STM's control ring serves dual purposes, acting as a manual focus ring when switched to that functionality. From a focus ring perspective, this tactilely distinct knurled plastic ring is tiny but positioned in front of the lens, where it is easy to find. This ring provides ideal rotational resistance, but adjusting the focus distance in tiny steps adds a challenge for establishing precise focus.
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's switch must be in the "MF" position and the camera meter must be on/awake for manual focusing to be available.
The RF 28's rate of focus distance change is dependent on the ring's rotation speed. A 330° slow rotation or 150° fast rotation provides a full extent adjustment. A linear adjustment rate is alternately available via a menu option in most R-series cameras.
Usually, the scene changes size in the frame as the focus is pulled from one extent to the other. This effect 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 significant change in subject size through a full-extent focus distance adjustment.
The RF 28's minimum focus distance is 6.3" (160mm), and it generates a mediocre 0.17x maximum magnification spec.
|Canon RF 15-30mm F4.5-6.3 IS STM Lens||5.1"||(130mm)||0.52x|
|Canon RF-S 18-45mm F4.5-6.3 IS STM Lens||7.9"||(200mm)||0.26x|
|Canon RF-S 18-150mm F3.5-6.3 IS STM Lens||6.7"||(170mm)||0.44x|
|Canon RF 24-50mm F4.5-6.3 IS STM Lens||11.8"||(300mm)||0.19x|
|Canon RF 24-105mm F4-7.1 IS STM Lens||5.2"||(131mm)||0.50x|
|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 EF-S 24mm f/2.8 STM Lens||6.3"||(160mm)||0.27x|
|Canon RF 28mm F2.8 STM Lens||9.1"||(230mm)||0.17x|
|Canon EF 28mm f/2.8 IS USM Lens||9.1"||(230mm)||0.23x|
|Canon RF 35mm F1.8 IS STM Macro Lens||6.7"||(170mm)||0.50x|
|Canon EF 40mm f/2.8 STM Lens||11.8"||(300mm)||0.18x|
|Canon RF 50mm F1.8 STM Lens||11.8"||(300mm)||0.25x|
A subject measuring approximately 8.0 x 5.4" (204 × 136mm) fills the imaging sensor at this lens's minimum MF distance.
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).
Often, a flat plane of sharp focus is not maintained at minimum focus distance, and the RF 28's corners show a slight softness. Still, this performance is good from a relative perspective.
Need a shorter minimum focus distance and higher magnification? Mount an extension tube behind this lens to significantly decrease and increase those respective numbers. 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. 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.
Small lenses use small amounts of materials, which inherently reduces costs and weight. With low material resources required, reasonable build quality can be maintained in a low-cost, lightweight lens.
This lens features a quality plastic external construction, with a metal mount.
The little knurled Control Ring can be configured for fast access to settings that include aperture, ISO, and exposure compensation. Move the Focus/Control switch to the MF position, and, as mentioned, this ring functions as the focus ring. MF and the Control Ring functionality cannot be used simultaneously, but sharing functionality means there is one less ring to confuse.
The Focus/Control switch is on a raised mount, and the switch is further raised just enough for easy use, even with gloves. This switch snaps crisply into position, with even the middle Control Ring setting easy to select. Note that this control ring turns smoothly — it is not clicked.
When fully focus extended, the lens barrel exhibits no play. Crescent-shaped black plastic guides protrude about 3mm behind the mount contacts, protecting the moving optical assembly from lateral impact when retracted. This lens will self-retract upon powering off if that option is enabled in the camera menu.
The RF 28mm lens is not weather sealed, and the front and rear elements are not fluorine-coated, a coating that repels dust and water drops and facilitates cleaning.
As already hyped, the Canon EF 24mm f/2.8 IS USM Lens is tiny and ultra-lightweight. Here is a table comparing the size and weight of numerous lenses.
|Model||Weight oz(g)||Dimensions w/o Hood "(mm)||Filter||Year|
|Canon RF 15-30mm F4.5-6.3 IS STM Lens||13.8||(390)||3 x 3.5||(76.6 x 88.4)||67||2022|
|Canon RF-S 18-45mm F4.5-6.3 IS STM Lens||4.6||(130)||2.7 x 1.7||(68.9 x 44.3)||49||2022|
|Canon RF-S 18-150mm F3.5-6.3 IS STM Lens||10.9||(310)||2.7 x 3.3||(69 x 84.5)||55||2022|
|Canon RF 24-50mm F4.5-6.3 IS STM Lens||7.4||(210)||2.7 x 2.3||(68.6 x 58.4)||58||2023|
|Canon RF 24-105mm F4-7.1 IS STM Lens||13.9||(395)||3 x 3.5||(76.6 x 88.8)||67||2020|
|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 EF 24mm f/2.8 IS USM Lens||9.9||(280)||2.7 x 2.2||(68.4 x 55.7)||58||2012|
|Canon RF 28mm F2.8 STM Lens||4.2||(120)||2.7 x 1||(69.2 x 24.7)||55||2023|
|Canon EF 28mm f/2.8 IS USM Lens||9.2||(260)||2.7 x 2||(68.4 x 51.5)||58||2012|
|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 EF 40mm f/2.8 STM Lens||4.6||(130)||2.7 x 0.9||(68.2 x 22.8)||52||2012|
|Canon RF 50mm F1.8 STM Lens||5.6||(160)||2.7 x 1.6||(69.2 x 40.5)||43||2020|
For many more comparisons, review the complete Canon RF 28mm F2.8 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:
Use the site's product image comparison tool to visually compare the Canon RF 28mm F2.8 STM Lens to other lenses.
A small lens usually gets narrow filter threads, and in this case, 55mm is the size. Filters of this size are small and affordable. Though not especially common, 55mm threads were featured on two recently introduced Canon RF-S lenses, the RF-S 18-150mm IS STM and 55-210mm IS STM.
Also small is the rugged aluminum Canon EW-55 Lens Hood, shown attached below.
The EW-55 screws into the lens's filter threads and provides replacement threads.
Sorry, the hood remains an optional accessory with Canon consumer-grade lenses, and the "Should I get the Canon RF 28mm F2.8 STM Lens hood?" is a valid question. The lens's front element is tiny, but it is exposed at the front of the lens. The EW-55 adds little to the size and weight of the lens while providing a significant level of, especially, impact protection to the front element. That benefit is countered with the EW-55's relatively high price.
The Canon LP811 Lens Case, a soft leather-like drawstring pouch with a reinforced and padded bottom, is also optional.
As one of the least expensive Canon RF lenses, the RF 28mm F2.8 STM Lens is a bargain. The image quality to price (and size and weight) ratio of this lens places it at the top of the best lens deals list.
As an "RF" lens, the Canon RF 28mm F2.8 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 28mm F2.8 STM Lens was online retail sourced.
The RF 28mm F2.8 STM fills the focal length gap between the RF 24mm F1.8 Macro IS STM and RF 35mm F1.8 IS STM Macro lenses. These two comparables have 1 1/3-stop wider apertures to their advantage. While small and light, they are considerably larger and heavier than the RF 28mm F2.8.
Let's compare the RF 28 to the RF 24 first. In the image quality comparison with wide-open apertures, the 28mm lens produces sharper results. Fairer is to compare at the widest common aperture. At f/2.8, the 24mm lens is slightly sharper in the center of the frame, and the 28mm lens is sharper in the periphery. The 24mm lens has more vignetting wide-open but less at f/2.8, and it has stronger barrel distortion.
Here is the Canon RF 28mm F2.8 STM Lens vs. RF 24mm F1.8 Macro IS STM comparison shows the 28mm lens weighing less than half as much and measuring well under half as long. The 24mm lens has 9 aperture blades vs. 7, in part because the wider aperture must be stopped down farther to reach the same narrow aperture opening, and more blades are required to keep blur shapes round. The 24mm lens has optical image stabilization, a considerably higher maximum magnification, 0.50x vs. 0.17x, and a significantly higher list price.
Nest up is the RF 28 comparison against the RF 35, one of Canon's first RF lenses. In the image quality comparison with wide-open apertures selected, the 28mm lens produces sharper results mid-frame and in the periphery. Compared at f/2.8, the 35mm lens is advantaged in the center, and the 28mm lens is slightly sharper in the periphery. The 35mm lens has more vignetting wide-open but far less at f/2.8. The 28mm lens has much stronger barrel distortion and shows slightly more flare effects.
Here is the Canon RF 28mm F2.8 STM Lens vs. RF 35mm F1.8 IS STM Macro comparison from a specifications perspective. The 28mm lens weighs about 40% as much as the 35mm lens and is much shorter. The 35mm lens has 9 aperture blades vs. 7, optical image stabilization, a considerably higher maximum magnification, 0.50x vs. 0.17x, and a significantly higher list price.
There are many additional comparisons available using the site's tools.
The Canon RF 28mm F2.8 STM Lens is an excellent add-on option for most kits.
While the strong barrel distortion is a detriment for this lens, the overall image quality it produces is remarkable, especially for the physical and pricing characteristics.
Select this lens when small, light, and affordable are high priorities but image quality can't be compromised.
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