Share your photographs...
We would love to feature your photographs on our equipment pages to help inspire others. We respect your copyright. Sharing is easy, just send us a link to your image on social media or your own website and remember to tell us about the following:
State that you own the copyright
Give us permission to use it
Include a link to your your web space
Include a caption for the image
Tell us about the equipment used
Review this item...
Tell us how you would rate it overall:
There are no reviews for this item
The Canon 17-40mm f/4 USM is an affordable L-series ultra-wide-angle zoom lens that's ideal for both film and digital SLRs. This EF lens focuses as close as 0.28m. It has a constant f/4 maximum aperture, and offers the choice of screw-in 77mm filters or a holder in the rear of the lens for up to 3 gel filters. The 17-40mm f4L also features a wear-resistant construction.
Key Features: Canon EF 17-40mm f/4 L USM Lens
Superb optical performance throughout the zoom range
Fast autofocus speed
Highly resistant to dust and moisture
28cm minimum focusing distance at all focal lengths
Ultra-wide or standard zoom
The EF 17-40mm f/4L USM acts as an ultra-wide angle zoom on film or full-frame digital EOS cameras. On DSLRs equipped with APS-C sized sensors it acts as a standard zoom, giving an angle of view equivalent to a 28-70mm lens on a full-frame camera.
Close focusing
Minimum focusing distance is just 28cm throughout the entire zoom range.
Superior optical performance
The EF17-40mm f/4L USM has 12 lens elements arranged in nine groups. Super Spectra coating ensures excellent colour balance and minimises ghosting and flare. To provide superb image quality over the complete 17-40mm zoom range the lens uses 3 aspheric elements. Super UD (Ultra-low Dispersion) glass prevents chromatic aberrations.
Ultrasonic focusing
A ring-type ultrasonic motor drives autofocus extremely quickly, and in near silence. Excellent holding torque ensures the point of focus is reached accurately, without overshooting. Furthermore, full-time manual override is available, making it possible to adjust focus without leaving AF mode.
Non-rotating front element
The front of the lens does not rotate, which makes using specialised filters, such as polarisers and graduates, easier. A drop-in gelatine-filter holder can be found at the back of the lens.
Smooth background blur
A virtually circular aperture diaphragm gives out of focus regions a softer, more uniform feel. Sharp foreground objects stand out against a smooth blurred background.
Weather resistant
Highly resistant to moisture and dust, the EF17-40mm f/4L USM is ideally suited for use in harsh environments. Environment friendly lead-free glass is used throughout its construction.
Attribute | Value |
---|---|
Aperture Blades: | 7 |
Autofocus Motor: | USM |
Colour: | Black |
Enlargement Ratio: | 1:4.2 |
Filter Thread Size (mm): | 77 |
Focal Length – Tele (mm): | 40 |
Focal Length – Wide (mm): | 17 |
Hood Model: | EW-83E |
Included Accessories: | Lens pouch, Front and rear caps, Lens hood |
Lens Mount: | Canon EF |
Lens Type: | Standard Zoom |
Manual Focus Switching: | Full Time Manual Override |
Maximum Aperture – Tele: | 4 |
Maximum Aperture – Wide: | 4 |
Minimum Aperture: | 22 |
Number of Lens Elements: | 12 |
Number of Lens Groups: | 9 |
Sensor Format: | Full Frame |
Size (mm): | 83.5 x 96.8 mm |
Weight (g): | 500 |
MF switch: | Full Time Manual Override |
Minimum Focus Distance (m): | 0.3 |