Compare lenses

Canon EF 17-40mm f/4L USM vs Tamron 17-35mm f/2.8-4 Di OSD

The Canon EF 17-40mm f/4L USM and the Tamron 17-35mm f/2.8-4 Di OSD side by side, computed from this guide's catalogue.

Which to pick

Pick the Tamron 17-35mm f/2.8-4 Di OSD if you want a brighter f/2.8 (1.0 stops more light), for dim light and softer backgrounds and a fit on more cameras (39 against 22 in this guide). On these specs the Canon EF 17-40mm f/4L USM has no clear advantage: choose it if the price, the handling or a lens you own decides it.

Still torn? Ask the guide about the Canon EF 17-40mm f/4L USM and the Tamron 17-35mm f/2.8-4 Di OSD

Specs side by side

Rows that differ are in full colour; the better value is marked where one is better by any measure.
Spec	Canon EF 17-40mm f/4L USM	Tamron 17-35mm f/2.8-4 Di OSD
Maker	Canon	Tamron
Focal length	17-40mm (zoom)	17-35mm (zoom)
Full-frame equivalent	17-40mm	17-35mm
Maximum aperture	f/4	f/2.8-4brighter
Made for	Full frame	Full frame
Mounts	Canon EF	Canon EF, Nikon F
Stabilised	no	no
Autofocus	yes	yes
Zoom range	2.4×more range	2.1×
Cameras it fits	22 in this guide	39 in this guidefits more cameras

Focal range, in full-frame terms

Canon EF 17-40mm f/4L USM: 17-40mm.

Tamron 17-35mm f/2.8-4 Di OSD: 17-35mm.

Aperture

Canon EF 17-40mm f/4L USM: f/4 wide open.

Tamron 17-35mm f/2.8-4 Di OSD: f/2.8 wide open.

Each opening drawn to scale against f/1.4: a smaller f-number lets in more light and blurs the background more.

Field of view

How wide each sees, at each end, on the sensor it was made for.

Cameras they fit

22 cameras in this guide take both, so either works on the same body. In all, the Canon EF 17-40mm f/4L USM fits 22 and the Tamron 17-35mm f/2.8-4 Di OSD 39.