Canon EF 17 40mm F 4L USM Review | 54 Data compared

The Canon EF 17-40mm f/4L USM is a high-quality, weather-resistant ultra-wide-angle zoom lens that delivers exceptional sharpness and an unusually broad "sweet spot" for performance between f/5.6 and f/8. Tested on an APS-C sensor (EOS-20D), it excels with excellent wide-open sharpness, very low chromatic aberration at mid-range focal lengths, and remarkably low vignetting under 1/4 EV. Its key pros include a constant f/4 maximum aperture, fast and silent ring-type USM autofocus, full-time manual focus, an 11-inch close-focus distance, and versatile filter options using 77mm screw-in filters or rear gel holders. However, cons on APS-C include moderate chromatic aberration at 17mm and rising levels at 40mm wide-open, alongside a slightly high 0.7% barrel distortion at the widest end. When paired with a full-frame sensor (EOS 5D), the lens faces significantly higher demands but remains a true bargain optic. A prominent con is significant corner softness when shooting wide open at f/4, though closing down just one f-stop to f/8 yields truly excellent, flattened corners. Full-frame usage also amplifies optical flaws, causing barrel distortion to hit 1% at 17mm, pincushion distortion to...

The Canon EF 17-40mm f/4 L is a lightweight, durable, and budget-friendly ultra-wide zoom lens optimized for full-frame cameras. A major highlight of the lens is its excellent center sharpness across all apertures and exceptional resistance to lens flare, making it highly effective for landscape and architectural photography where the sun is often in frame. It also features a professional L-series build quality with a standard 77mm filter thread, facilitating easy filter sharing with other professional Canon gear. The lens performs best when mounted on a tripod and stopped down to smaller apertures, which helps maintain deep depth of field. However, the lens suffers from notable corner softness and chromatic aberrations when shot wide open at its maximum f/4 aperture. Because it lacks image stabilization (IS) and a faster f/2.8 aperture, it is less ideal for handheld, low-light street or event photography compared to pricier alternatives like the EF 16-35mm series. Furthermore, the reviewer notes that the 17-40mm is merely mediocre on cropped-sensor (APS-C) bodies. On a crop sensor, users are restricted by diffraction blur at narrower apertures, and the...

Ken Rockwell praises the Canon 17-40mm f/4 L as an exceptional, high-utility lens for full-frame cameras, highlighting its superior ergonomics, durable construction, and lightweight design. It is lauded as a high-value option that delivers stellar optical performance without the cost or weight of faster alternatives. However, the lens is less suited for 1.6x crop-sensor cameras, where its size causes shadows from built-in flashes, and its f/4 aperture may limit performance in extreme low-light situations.

The Canon EF 17-40 mm f/4.0L USM is an ultra wide-angle lens introduced in 2003 for 35 mm full-frame sensors, which quickly became a popular upgrade for APS-C DSLR shooters seeking an L-grade substitute for standard kit lenses. In their comprehensive review, LensTip highlights several standout advantages, including very good image resolution at both the center and edges of the frame, excellent control over chromatic aberration, and low levels of distortion, coma, and astigmatism. Additionally, the lens boasts highly robust build quality, minimal vignetting, strong performance when shooting into bright light, a fast, quiet Ultrasonic Motor (USM) autofocus system, and a highly reasonable price point relative to its performance. Despite the overwhelmingly positive characteristics, LensTip outlines a couple of minor drawbacks for potential buyers to consider. The reviewers note that while the autofocus is quick, the USM motor could occasionally make fewer focus mistakes. Furthermore, given its positioning within Canon's premium, professional-grade "L" lineup, the testing team concluded that they ultimately expected slightly higher absolute resolution figures from the optic. LensTip.com

The Canon EF 17-40mm f/4L USM Lens Review highlights the lens as a durable, weather-sealed, and relatively affordable L-series option featuring fast, quiet, and accurate Ring USM autofocus, alongside a fixed-length barrel design that is ideal for users of circular polarizers. The review praises the lens for its impressive center sharpness, excellent color and contrast, and strong resistance to flare. Key limitations include significant corner softness when shooting wide-open at f/4, with optimal performance requiring stopping down to at least f/5.6. Additionally, the review notes the constant f/4 maximum aperture limits low-light capability, and full weather sealing requires the addition of a front UV filter.

The PCMag review rates the Canon EF 17-40mm f/4L USM as a 3.0 out of 5 "Average" lens, positioning it as an affordable, budget-friendly alternative to premium ultra-wide zooms for full-frame shooters. It features a constant f/4 aperture, a fast and silent ultrasonic focusing motor, and produces strong center sharpness, with performance improving towards the 40mm focal length. However, the lens suffers from notable compromises, including muddy edges and corners at 17mm, visible barrel distortion, and color fringing. While stopping down to f/5.6 improves image quality, the 17-40mm f/4L is deemed best for budget-conscious photographers, whereas those requiring sharp edge-to-edge performance are advised to choose the 16-35mm alternative.

The Canon EF 17-40mm f/4L USM is a lightweight, professional-grade wide-angle zoom lens that offers a portable and moderately priced alternative to faster f/2.8 variants. Scoring 21 points on DxOMark, it is noted for very good sharpness at the wider end with excellent uniformity across the field when wide open. Its high-grade optical construction includes three aspherical elements and Super-UD glass, allowing for a close minimum focusing distance of 11.02 inches. While it was originally designed for full-frame sensors, it remains a popular choice for APS-C users as a 27-64mm equivalent lens. However, the review highlights several performance trade-offs, specifically a drop in sharpness at focal lengths of 35mm and above when used at the maximum aperture. While chromatic aberration is well-controlled in the 24-40mm range, it becomes evident in the extreme corners at 17mm on full-frame cameras. Despite these issues, the lens holds its own against the significantly more expensive 16-35mm f/2.8L II USM, offering more uniform sharpness and similar peak performance when stopped down to f/8-11. Ultimately, its small size and high portability make it a recommended choice...

The Canon 17–40mm f/4L USM lens, reviewed in.RAW Magazine, is presented as a versatile, lightweight, and affordable L-series option suitable for landscape photography on both cropped and full-frame sensors, featuring fast USM autofocus and robust weather sealing. Key advantages include good sharpness across the frame and a manageable 500g weight, positioning it as a high-value, professional-tier choice. Conversely, the review notes significant performance drawbacks, including severe distortion and a substantial drop in sharpness at the edges when shooting wider than 20mm. Additionally, the constant f/4 maximum aperture limits the lens's effectiveness in low-light scenarios compared to faster alternatives.

The Canon EF 17-40mm f/4L USM lens provides an upgrade path to full-frame systems but functions as a general-purpose zoom when mounted on a cropped-frame APS-C body. On cropped bodies, its primary advantages include superior "L" series build quality, exceptionally smooth manual focus and zoom rings, and high optical performance that delivers sharp, high-contrast images with minimal color fringing. Additionally, it features a fast, quiet USM internal focusing motor, a constant f/4 maximum aperture across the entire zoom range, and includes a lens hood and pouch as standard accessories. However, the lens has notable drawbacks when used as a single-lens solution for APS-C cameras. Its 17-40mm focal range is shorter than standard kit lenses, meaning it lacks the zoom reach required for many general-purpose situations. It also lacks Image Stabilization, making alternative options like the EF-S 17-85mm more flexible and practical for daily use on compatible cropped bodies. Ultimately, this lens is recommended mainly for cropped-frame owners who already possess separate lenses to cover longer focal lengths and who plan to upgrade to a full-frame body in the future.

The Canon EF 17-40mm f/4L serves as a lighter, more budget-friendly full-frame alternative to the premium 16-35mm f/2.8L II, making it a highly attractive option for photographers who want the durable build of a professional "L" series lens without the high price tag. Built with an all-metal body and internal focusing mechanism, the lens is highly durable and pairs exceptionally well with APS-C crop-sensor bodies, where its apparent focal length shifts to a versatile 27-64mm while masking edge-softness flaws. Its 77mm filter thread keeps accessory costs low, and its fast, accurate autofocus makes it highly functional for photojournalists, event coverage at f/5.6, stopped-down landscape work, and interior architecture photography where lines can be straightened during editing. However, choosing this lower-priced alternative introduces several optical compromises, particularly when shooting wide-open at f/4. The review highlights major cons including noticeable vignetting, chromatic aberration (fringing) at the corners of full-frame sensors, and a general lack of sharpness until stopped down to f/5.6. Heavy lens distortion is also prominent across the entire focal range, creating a particular challenge for architectural work that necessitates destructive...