The Canon RF-S 10-18mm F4.5-6.3 IS STM lens is an excellent choice for beginners who own APS-C EOS R mirrorless cameras. It is more comprehensive than the available kit options, performs well, and is quite compact. It is also quite affordable, making it an excellent entry-level option. However, the narrow aperture and lack of weather sealing limits the lens’ use in harsh conditions and dim light. It works well with the Canon’s starter cameras, such as the RF-S 18-45mm. No other ultra-wide, crop-sensor zooms with autofocus are available for the system. If you are comfortable with manual focus, you can consider the wider, slightly brighter Venus Optics Laowa 8-16mm F3.5-5 CF for $549. We haven’t tested the 8-16mm, but we have enjoyed other optics from the brand.
Wide-Angle Views and Basic Features
The RF-S 10-18mm F4.5-6.3 lens is budget-friendly and has a plastic construction with glass optics. Unfortunately, it lacks weather protection and on-barrel function buttons. Additionally, there is no lens hood included in the box, but a compatible EW-53B hood can be purchased from Canon for $29. If you want to add a protective or ND filter, it supports the 49mm thread size.
The plastic build of this lens makes it small and lightweight, which is great for matching with basic Canon mirrorless bodies like the EOS R50, R100, and R10. It only weighs 5.3 ounces and measures 1.8 by 2.7 inches (HD) when collapsed. Although it extends slightly longer when you zoom in, there is no lock or button to deal with. A simple twist is all it takes to switch between the collapsed and ready-to-shoot configurations.
The lens has a 1.8x range which is equivalent to a 16-29mm full-frame zoom. Its starting angle is just on the edge of what is considered ultra-wide, and it is slightly narrower than the iPhone 15’s 0.5x lens (13mm equivalent), for reference. Overall, this lens is great for capturing architectural interiors, cityscapes, and landscapes. It’s also suitable for taking selfies and shooting vlogs from an arm’s length.
As mentioned earlier, both the RF-S 18-150mm and 18-45mm F4.5-6.3 IS lenses do not offer a very wide view. Canon also offers a compact 10-20mm F4 lens for full-frame cameras, which costs $2,299 and may be too expensive for most APS-C camera users. However, the RF 16mm F2.8 is an excellent and affordable lens to consider if you need a slightly wider angle than your kit zoom lens. Moreover, you can take this lens with you if you upgrade to a full-frame Canon camera later.
Autofocusing third-party lenses are not yet available for the EOS R camera, leaving users with limited options. However, the Sigma 10-18mm F2.8 DC DN Contemporary lens designed for Fuji and Sony cameras priced at $599 could be a viable alternative if it is made compatible with the RF mount. Canon has indicated in a recent interview with PetaPixel that it is currently negotiating with third-party manufacturers, so it is worth waiting to see what happens if you’re not happy with the narrow aperture of the RF-S 10-18mm.
If you’re willing to take on the challenge of using a full-time manual focus lens, you may want to consider the Venus Optics Laowa 8-16mm F3.5-5 mentioned earlier. Although manual focus may seem daunting to beginners, it’s not difficult to achieve with an electronic viewfinder (EVF) and there’s plenty of room for minor misfocusing when using an ultra-wide lens. TTArtisans also offers the fixed-angle 10mm F2 for only $159, but I have not yet had the opportunity to test it.
To enjoy autofocus, you have the option to use the EF-EOS R adapter with older EF-S SLR lenses. If you are looking for something more midrange than entry-level, the Tamron 10-24mm F3.5-4.5 Di II VC HLD is a great choice. However, you might need to navigate the used market to find it.
Easy Handling and Minimal Controls
There’s not much to the RF-S 10-18mm in terms of on-barrel control. As expected, Canon leaves off the toggle switches and function buttons of high-dollar lenses. The zoom ring takes up most of the space here and is easy to find thanks to its ribbed plastic texture. A painted dot indicates when the zoom is in its retracted position, while focal length markings appear at 10, 12, 14, 16, and 18mm.
A slim, diamond-knurled function ring sits just ahead of the focus ring. In autofocus mode, its function is configurable. You can set it to handle aperture, EV compensation, ISO, shutter, and white balance adjustments, in addition to dozens of other options. If you set the body to manual focus, the function ring automatically switches over to focus control.
The autofocus response is snappy, accurate, and quiet enough to use for video along with the in-camera mic. Manual focus is a bit touchy, however, regardless of whether you set the camera body for a linear or nonlinear response. In either case, the focus drives too quickly for minute adjustments. You’re better off using autofocus full-time.
“I don’t think this zoom is suitable for indie film projects, but it’s great for self-recording vloggers because of its wide view and effective optical stabilization. Additionally, I didn’t notice any blooming or shrinking of the frame from focus shifts (known as focus breathing). For walk-and-talk footage, I suggest enabling digital stabilization in your camera, despite the slight crop that mode adds. In case you want to add a powered gimbal to your crop-sensor kit, the small DJI RS 3 Mini is a suitable choice.”
I recently tested a lens with the EOS R7 camera body, which has a stabilized sensor. When used together, the lens and camera stabilization systems can support up to six stops of compensation. However, the EOS R10, R50, and R100 only rely on the lens’ stabilization, which means you can expect up to four stops on those. During my close-up, handheld tests at both the wide and long ends, I was able to capture images without any motion blur caused by camera shake at 1/2-second shutter speed consistently. At 1-second shutter speed, the results were hit-or-miss. This is great news for those who enjoy taking long-exposure photos without a tripod.
The lens has a close focus capability, allowing you to take wide-angle macro shots. The best macro photos can be achieved at 18mm with autofocus. At this focal length, the lens has a minimum focus distance of 5.5 inches, resulting in a life-size reproduction of 1:4.3. If you switch to manual focus and zoom out to 10mm, the focus distance decreases to 3.4 inches, resulting in a half-size magnification. However, since lens macro distances are measured from the sensor, there is only a small distance between the front glass and the closest focus point at 10mm, which can make it difficult to avoid casting a shadow or creating perspective distortion. Nonetheless, this effect can be useful for certain scenes, particularly if you are interested in creating a grotesque effect, which can cause features and shapes to stretch unnaturally.
RF-S 10-18mm: In the Lab
I tested the 10-18mm lens with the 33MP EOS R7 camera to evaluate its optical performance in both the lab and the field. For contrast-based resolution testing, we used Imatest and an SFRplus test chart. The lens delivers consistent performance throughout its focal range, achieving very good results (3,500-3,700 lines) for the R7’s sensor when used at f/4.5-8. However, image quality begins to deteriorate at smaller f-stops due to optical diffraction. Essentially, when light particles pass through a very small opening or aperture, as is the case with a closed-down aperture, they scatter, causing a softening effect.
Despite the loss of detail, some creators look to narrower apertures to create the sunstar effect. It’s the result of diffraction—extra bright areas of a photo, like the sun, take on the shape of the aperture as they pass through and render as multi-point starbursts. Forgive the pun, but the 10-18mm isn’t an all-star here. Its 14-point bursts don’t have crisp tines and introduce some false color.
In general, the RF-S 10-18mm struggles when it comes to capturing pictures against a strong backlight. It’s prone to false color and flare, even wide-open. Contrast holds up pretty well, but the ghosting can be ugly and distracting. If you tend to go out on sunny days, I recommend picking up the optional hood. It’s overpriced, but I couldn’t find an aftermarket alternative at press time.
Automatic in-camera corrections can fix barrel distortion and vignetting, which means that your JPGs and videos will show straight lines and even illumination across the frame. However, if you prefer using raw format, make sure that your image processor has a correction profile. Adobe Lightroom Classic, which is our standard for camera and lens reviews, applies the correction profile automatically. But if you decide not to use corrections for raw images, you can get a wider view of the scene, although there may be a slight fisheye bulge and blurry corners. Nonetheless, this effect can be used artistically.
The lens has a wide angle of view and a narrow aperture, making it easier to capture scenes with a large depth of field. However, you can still blur backgrounds at macro ranges. The amount of softening is slight overall, and in many situations, background objects can be identified without any issue. Although there is a bit of false color (longitudinal chromatic aberration) in the backgrounds, it is not a major problem. On the other hand, lateral chromatic aberration, which appears as color fringing in high-contrast areas on the plane of focus, is more visible. But, it is not overly problematic. If you notice this effect in a photo, you can try narrowing the f-stop or using a tool like Lightroom’s Defringe slider to fix it.
Competent, If Unexciting
The RF-S 10-18mm F4.5-6.3 IS STM lens is a great choice for beginner photographers who are using a crop-sensor Canon mirrorless camera. Although it may not have the most impressive specifications, it provides reliable performance and is easy to carry around. It has a wider angle than the 18-45mm or 18-150mm kit lenses, focuses quietly, and has effective stabilization. Additionally, it is very affordable. The fact that it has a narrow aperture range and may produce flares aren’t big issues, especially since there aren’t any other first- or third-party options that have autofocus and cover the same range at a comparable price. If you want to try out wider angles, don’t hesitate to get this lens. However, if you’re willing to use manual focus, the Laowa 8-16mm F3.5-5 CF is a good alternative. While we haven’t reviewed it yet, we have given high ratings to other lenses from the same company.
