A Review of the Impressive Canon RF 10-20mm F4 L IS STM Lens

Ultra-wide angle lenses are beloved for their ability to capture expansive scenes. One standout option is the Canon RF 10-20mm F4 L IS STM lens, and this great video review takes a look at the performance and image quality you can expect from it. 

Coming to you from Christopher Frost, this detailed video highlights the capabilities of the Canon RF 10-20mm f/4 L IS STM lens. With a zoom range from 10mm to 20mm, this lens offers versatility for various shooting scenarios. Most ultra-wide zoom lenses start at 16mm, but this lens takes it further, providing a particularly wider field of view. This is especially useful for architecture, landscapes, and indoor photography. 

The build quality of the lens is noteworthy. Made from high-quality plastic, it's lightweight yet durable. And weighing only 570 grams, it feels comfortable in hand. The lens includes a customizable button, autofocus, and image stabilization switches. The zoom and focus rings are smooth, making them ideal for video work. The autofocus motor is silent, accurate, and fast, ensuring you capture sharp images quickly.

Image quality is a crucial aspect of any lens, and the RF 10-20mm does not disappoint. On a full frame camera like the EOS R5, it delivers sharpness and contrast across the frame. Even at the widest setting of 10mm, the lens performs admirably. While there is some softness at the edges, the overall sharpness remains impressive. The lens maintains this quality down to f/11, where diffraction begins to soften the image. At 20mm, sharpness remains excellent in the center, with slight softness at the edges.

When using the lens on an APS-C sensor camera, like the Canon EOS R7, the performance remains strong. The lens handles the high-resolution sensor well, maintaining sharpness in the center even at 10mm. The corners are softer but still usable. Stopping down the aperture improves sharpness, but diffraction becomes more noticeable at smaller apertures.

One challenge with ultra-wide lenses is distortion and vignetting. The RF 10-20mm exhibits noticeable barrel distortion and vignetting at 10mm. These issues are correctable in post-processing, but they highlight the lens' optical design challenges. At 20mm, the distortion is less pronounced, and vignetting is manageable by stopping down the aperture.

Close-up performance is another area where this lens shines. With a minimum focus distance of 25 cm, it captures sharp images even at f/4. The lens performs well against bright lights, maintaining high contrast and minimal flaring. Coma is well-controlled, making it suitable for night photography.

Overall, the Canon RF 10-20mm F4 L IS STM lens is a remarkable ultra-wide zoom option. While there are some optical quirks, the lens' strengths far outweigh its weaknesses. Check out the video above for the full rundown from Frost.