The Canon RF 15-35mm F2.8L IS USM is a professional-grade ultra-wide-angle zoom lens designed for full-frame cameras. This lens offers an extensive focal range, robust build quality, and advanced features that cater to landscape, architecture, cityscape, and travel photographers. Despite its hefty price tag, it competes well with similar offerings from other brands and provides excellent image quality. However, it relies heavily on in-camera corrections to achieve optimal results.

A Comprehensive Professional Tool

This section delves into the design and construction of the Canon RF 15-35mm F2.8L IS USM. The lens is built to withstand challenging environments, featuring weather sealing and durable materials. Although it is heavier than some might expect, it balances well with full-frame camera bodies. The inclusion of features like optical image stabilization and a short minimum focus distance enhances its versatility for various shooting scenarios.

The RF 15-35mm F2.8L IS USM is crafted with precision, incorporating 16 elements in 12 groups, including three aspherical and two UD elements. The fluorine-coated front element ensures durability and ease of cleaning. The lens also includes a control ring that can be programmed for in-camera adjustments, adding flexibility for users who prefer customized settings. While the weight might be a concern for some, the overall build quality and robust design make it a reliable choice for professionals. The internal focusing mechanism prevents the front element from rotating, which is beneficial for using filters, but the non-internal zoom design means the lens extends when adjusting the focal length.

Exceptional Performance with Caveats

The performance of the Canon RF 15-35mm F2.8L IS USM is impressive, particularly in low-light conditions thanks to its constant f/2.8 aperture and 5-stop optical image stabilization. The autofocus system is fast and silent, making it suitable for both stills and video. The lens excels in capturing sharp images with good edge-to-edge resolution, especially when used with lens corrections enabled. It also produces stunning sunstars around artificial light sources at night, enhancing its appeal for night photography.

However, the reliance on lens corrections is notable. When shooting in raw format, Lightroom automatically applies corrections for chromatic aberration and profile distortions. Without these corrections, images exhibit vignetting and slight optical distortions, such as barrel distortion at wider angles and pincushion distortion at longer focal lengths. Chromatic aberration is minimal but can appear along high-contrast edges. Despite these drawbacks, the overall image quality remains high, and the lens performs exceptionally well for its intended use cases. For those seeking a premium ultra-wide-angle lens, the RF 15-35mm F2.8L IS USM delivers outstanding results, albeit with a few compromises in uncorrected raw files.