About this model
The Canon EF 17-40mm f/4L USM is an ultra-wide zoom from Canon's professional L series, and for years it was one of the more affordable ways into L-series glass. On a full-frame body it covers a dramatic 17mm wide-angle to a natural 40mm, well suited to landscapes, architecture, interiors and events. The constant f/4 aperture keeps exposure consistent as you zoom, while the ring-type USM motor focuses quickly and quietly with full-time manual override. Built to L-series standards with weather sealing, it is a tough, dependable lens that pairs neatly with a standard zoom for a lightweight two-lens kit.
Key specs
| Type | Ultra-wide-angle zoom lens (Canon L series) |
|---|---|
| Focal length | 17–40mm |
| Maximum aperture | f/4 (constant) |
| Mount | Canon EF |
| Format | Full frame (also fits APS-C, approx. 27–64mm equivalent) |
| Autofocus | Ring-type USM with full-time manual focus |
| Image stabilisation | No |
| Weather sealing | Yes |
| Filter size | 77mm |
| Minimum focus distance | 0.28m |
| Weight | approx. 475g |
Compatibility
Fits all Canon EF-mount DSLRs, full-frame and APS-C (EF-S). Works on Canon RF mirrorless cameras (EOS R series) with the Canon EF-EOS R adapter, and on EOS M cameras with the EF-EOS M adapter, keeping autofocus.
Questions about this model
Will the Canon 17-40mm f/4L fit my camera?
It fits every Canon EF and EF-S DSLR, and Canon mirrorless (EOS R and EOS M) cameras with the official Canon adapter.
Is the 17-40mm f/4L weather sealed?
Yes, it is built to L-series standards with weather sealing.
Is the 17-40mm f/4L good for landscapes?
Yes. Its 17mm wide end and constant f/4 aperture make it a popular, lightweight choice for landscapes and interiors.
