Ever since Canon first introduced their EF 11-24mm f/4L lens back in 2015, it has been the pinnacle of ultra wide-angle zooms for many shooters. With a constant f/4 aperture across a generous 11-24mm range, pro-grade weather sealing, and excellent optics, it has been a workhorse lens for landscapes, real estate, events, and more.
However, the increasing popularity of Canon’s RF-mount mirrorless system created a demand for a new and improved ultra-wide zoom specifically designed to unlock the full potential of the short flange distance RF mount. Enter the Canon RF 10-20mm f/4L IS STM, sitting at the exotic and highly desirable 10mm end of the spectrum while still offering a versatile zoom range. Complimenting cutting-edge optics is 5-stop optical image stabilization, fast and reliable autofocus, and a compact lightweight design.
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Canon RF 10-20mm F4L IS STM lens Review
Canon RF 10-20mm F4L IS STM lens ReviewCanon RF 10-20mm f/4L IS STM Lens Review
As a landscape, architecture, and real estate photographer, I’ve been eager to test Canon’s fast new 10-20mm ultrawide zoom lens for their mirrorless RF mount. After extensive real-world use, I can confidently say the RF 10-20mm f/4L IS STM takes full frame wide-angle shooting to a new level.
Canon RF 10-20mm f/4L IS STM Key Takeaways:
- Class-leading 10-20mm ultrawide zoom range
- Jaw-dropping perspectives at 10mm, 130° maximum angle of view
- Excellent corner-to-corner sharpness even at 10mm and f/4
- Fast, quiet STM autofocus optimized for stills and video
- 5 stop optical image stabilization (6 with IBIS camera)
- Customizable control ring and function button
- L-series weather sealing in a surprisingly compact form
- Great for landscapes, real estate, architecture, astrophotography
Handheld Shooting Experience
Weighing just 1.25 pounds, the RF 10-20mm delivers outstanding handheld shooting. I hiked and explored all day with it across cities and national parks. The compact size never felt bulky or strained my wrists. Smooth focusing and zoom rings provide a secure grip. The wonderful balance on EOS R bodies made framing effortless. I walked away with fantastically sharp landscapes and interiors.
Optical Quality & Sharpness
This lens delivers outstanding resolution and clarity across the zoom range. Photos are crisply detailed at 10mm and f/4, with incredible sharpness from center to edges. By f/8, images are tack sharp, able to resolve the finest details. Advanced coatings virtually eliminate flare and ghosting when shooting into sunlight. Distortion is impressively controlled despite the extreme angle of view, keeping lines straight.
Canon’s expertise with specialized glass elements is evident in the amazing results. Their use of aspherical, UD and Super UD lenses achieves unreal sharpness with vibrant, accurate color rendition. This level of optical quality exceeds much more expensive wide-angle lenses.
Autofocus Performance
The STM autofocus provides smooth, quick and near silent focus perfectly suited for stills and video work. Face tracking performed excellently for environmental portraits. The lens snapped into focus instantly for landscape shots. Focus transitions are pleasingly gradual during video recording. The AF is responsive enough for moving subjects but not designed for fast action.
Image Stabilization
Having up to 5 stops of optical image stabilization allows me to capture handheld low light scenes once impossible without a tripod. I could easily shoot sharp interior real estate images at 1/15 second shutter speeds thanks to the highly effective IS. On IBIS camera bodies, the dual stabilization provides a combined 6 stops of shake reduction, letting me handhold slow exposures down to 1 second at 10mm.
For video work, the stabilization delivers gimbal-like smoothness when moving through a scene. For both stills and video, this degree of IS vastly expands my creative opportunities.
Ergonomics & Design
Despite its pro-grade quality, the RF 10-20mm remains highly compact and portable at just 4.4 inches long when retracted. Outstanding weather sealing provides protection when shooting in dusty or wet environments. Small details like the customizable control ring, fluorine coating, and lockable zoom ring demonstrate thoughtful design. The lens is a joy to shoot with for extended periods.
Weather Sealing
As an L-series lens, the RF 10-20mm features robust sealing to protect against dust and moisture. The lens mount gasket, button, and rings use dense rubber sealing. I used the lens in light snow and rain with no sign of water intrusion. I have full confidence in using this lens to capture landscapes in harsh conditions.
Ideal Uses
This lens shines for:
- Sprawling landscape scenes
- Interiors and exteriors in real estate
- Architectural photography
- Astrophotography and Night Skies
- Vlogging and video B-roll
- Wedding and event venues
- Immersive perspectives across genres
Canon RF 10-20mm f/4L IS STM Pros and Cons
Pros
- Incredible 10mm max angle of view
- Superb optics and sharpness
- Effective 5 stop optical stabilization
- Fast, smooth STM autofocus
- Compact and lightweight design
- L-series weather sealing
- Customizable control ring and function button
Cons
- Noticeable distortion at 10mm
- Only f/4 max aperture
- Lens hood not included
- High price, but justified
Canon RF 10-20mm f/4L IS STM Review Final Verdict
For Canon RF mount shooters needing to go wider, this lens is simply incredible. The 10-20mm focal range enables unique perspectives perfect for landscapes and architecture. Image quality is outstanding across the zoom range with exemplary sharpness and clarity. The stabilisation expands creative options dramatically. While expensive, the performance exceeds expectations. If you need to capture jaw-dropping wide-angle views, look no further. This lens earns my highest recommendation.
Canon RF 10-20mm f/4L IS STM FAQ
How does this compare optically to Canon’s EF 11-24mm f/4L lens?
The RF 10-20mm matches or slightly exceeds the legendary EF 11-24mm in sharpness, distortion control, and overall image quality from 11-20mm. The RF version adds stabilization, closer focusing, and improved flare resistance. With a wider max angle of view, the RF lens unlock perspectives the EF can’t achieve.
Is the Canon RF 10-20mm weather sealed?
Yes, as with all L-series lenses, it features extensive sealing against dust and moisture. The mount, rings, buttons, and joints are thoroughly sealed for protection in harsh conditions.
Does this lens have quiet autofocus for video?
Definitely. The STM motor provides smooth, quiet autofocus optimized for video work. Focus transitions and rack focusing are gradual and near silent.
What are the best camera options to pair with this lens?
Any Canon EOS R series body will work well, but higher resolution models like the R5 and R6 best take advantage of the lens’ outstanding optics. Having a body with IBIS enables the full 6 stops of stabilization.
Is the lens easy to carry for extended periods?
Absolutely. At just 1.25 pounds, the RF 10-20mm is remarkably lightweight and compact for an L-series zoom. Photographers will have no issues carrying this in the field all day.
