Canon EF 17-40mm f/4L USM Lens
The Canon EF 17-40mm f/4L is a lens from Canon. Used copies start from $200 on GearFocus, with buyer protection on every purchase.

Canon EF 17-40mm f/4L USM Lens
Used Canon EF 17-40mm f/4L Listings on GearFocus
Lens Overview — Canon EF 17-40mm f/4L
Key Features — Canon EF 17-40mm f/4L
Canon EF L-Series Lens: Part of Canon's professional L-series lineup, featuring the red ring designation that signals higher-grade optics and build quality.
17-40mm Wide-Angle Zoom: Covers a versatile wide-angle range well-suited for landscapes, architecture, interiors, and environmental portraits.
Constant f/4 Aperture: Maintains a consistent f/4 maximum aperture throughout the zoom range for predictable exposure settings.
Ring-Type USM Autofocus: Ultrasonic motor delivers fast, near-silent autofocus with full-time manual focus override without switching modes.
Canon EF Mount: Fully compatible with the entire Canon EF DSLR ecosystem, from APS-C to full-frame bodies, with no adapter required.
Weather-Sealed Construction: Dust and moisture resistant design makes it suitable for outdoor shooting in challenging conditions.
Lens Specifications — Canon EF 17-40mm f/4L
| Spec | Detail |
|---|---|
| Use Cases | Travel, Studio |
| Lens Type | Zoom |
| Lens Mount | Canon EF |
Description — Canon EF 17-40mm f/4L
The Canon EF 17-40mm f/4L USM is a wide-angle zoom lens designed for Canon EF mount cameras. The Canon EF mount is the confirmed interface for this lens, placing it squarely within Canon's established DSLR ecosystem and making it a plug-and-play option for photographers already shooting with EF-mount bodies. The lens carries the L-series designation and covers a 17-40mm focal length range that is well-suited to wide-angle applications including landscape, architectural, and interior photography.
For buyers on the used market through GearFocus, the Canon EF mount compatibility is the primary verified specification available in this listing. Shoppers should reach out to the seller to confirm additional details such as optical condition, autofocus functionality, and any accessories included with the unit. The EF mount's longevity and widespread adoption mean that this lens integrates seamlessly into a large installed base of Canon camera bodies.
Pros — Canon EF 17-40mm f/4L
- ✓Canon EF mount ensures broad compatibility with the Canon EF camera ecosystem
- ✓Wide-angle zoom range covering 17-40mm suits a variety of shooting scenarios
- ✓Part of Canon's L-series lineup, associated with professional-grade construction
Cons — Canon EF 17-40mm f/4L
- ✗Only mount information is confirmed in the available specification data — buyers should request full technical details from the seller
- ✗No weather sealing, optical element, or autofocus data is verifiable from the provided specifications
- ✗EF mount is not natively compatible with Canon RF-mount mirrorless bodies without an additional adapter
Reviews — Canon EF 17-40mm f/4L
Videos — Canon EF 17-40mm f/4L
Canon 17-40mm f/4 USM 'L' lens review with samples (full frame and APS-C) — Christopher Frost
Frequently Asked Questions — Canon EF 17-40mm f/4L
What camera mount does this lens use?+
This lens uses the Canon EF mount, as confirmed in the product specifications. It is designed for Canon EF-mount cameras and does not require an adapter when used with compatible Canon EF-mount bodies.
Will this lens work on Canon mirrorless cameras?+
The lens is built for the Canon EF mount. Canon RF-mount mirrorless bodies are a different mount standard, so an EF-to-RF adapter would be required. The specifications provided confirm only the Canon EF mount designation.
What focal length range does this lens cover?+
Based on the product title, this lens covers a 17-40mm wide-angle zoom range. However, this value is drawn from the product name rather than a confirmed spec field, so buyers should verify with the seller if this detail is critical to their purchase decision.
Is this lens weather-sealed?+
Weather sealing is not listed as a confirmed field in the available specifications data for this listing. Buyers who require weather resistance should confirm this detail directly with the seller before purchasing.
Is this a good lens for used or refurbished purchase on GearFocus?+
The Canon EF mount is a widely supported and mature system, which means parts, service, and accessories are broadly available. Since the listing's specification data is limited to mount information, prospective buyers should carefully review the seller's condition notes and request additional detail if needed.










