Canon EF 17-40mm F4 L USM Review

General information

This is a zoom lens manufactured by Canon and the lens was released 2003.
The lens belongs to the category wide angle zoom lenses, a wide angle lens where you have the possibility to zoom in and out.

Product description from Canon

At launch 2003 Canon wrote this regarding Canon EF 17-40mm F4 L USM :

"A new and affordable L-series ultra-wide-angle zoom lens thatīs ideal for both film and digital SLRs. Superior optics are assured by the use of three Aspherical lens elements, in addition to a Super UD (Ultra-low Dispersion) glass element. Optical coatings are optimized for use with digital cameras. This lens focuses as close as 11 inches (0.28m), and offers both Canonīs full-time manual focus and a powerful ring-type USM for fast and silent AF. 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 three gel filters. Finally, it offers weather-resistant construction similar to other high-end L-series lenses.

The EF17-40mm f/4L USM was developed as high-end version of the highly acclaimed EF20-35mm f/3.5-4.5 USM lens released in March 1993. Designed for use by professional and amateur users alike, this lens realizes the outstanding image resolution that distinguishes an L-series lens while retaining high cost performance. Featuring a new optical system design, the new lens delivers an expanded zoom range of 17-40mm, with the wide-angle-end 17mm focal length making it ideally suited to digital photography.

The EF17-40mm f/4L USM utilizes a combination of one high-precision molded glass aspherical lens and two replica aspherical lenses to achieve the extended zoom range, while also correcting for a variety of aberrations that arise during zooming. Moreover, a Super UD (ultra-low dispersion) glass element minimizes the chromatic aberration of magnification that tends to occur with wide-angle lenses, eliminating color bleed along the edges of the subject and realizing high image contrast and resolution.
The 17 mm focal length achieved by the EF17-40mm f/4L USM lens also extends wide-angle shooting potential when paired with digital AF SLR cameras, such as the high-end amateur-model EOS 10D , which have smaller imaging areas than 35 mm film. Taking into account the smaller angles of view that result, the new lens realizes a focal range equivalent to 27-64mm in the 35mm format (or 1.6 times) when paired with EOS 10D.

Moreover, the power of the focusing lens group has been increased to allow a minimum focusing distance of just 0.28 meters throughout the entire zoom range. The EF17-40mm f/4L USM also features a circular diaphragm for improved background blur, and utilizes only lead-free glass optics in consideration of the environment.The new lens features a hardy water- and dust-resistant construction,ensuring professional users unfailing performance under even the most grueling of conditions."


Compatibility, autofocus and focal length

This lens is constructed to fit all models of Canon cameras, regardless of camera model or type of sensor.

The ability to use autofocus is available for all cameras.

The lens has a focal length of 17-40 mm. Depending on which camera the lens is used, the experienced and perceived focal length will be different. Please visit the list of compatible cameras below, it will provide the equivalent focal length you get on each camera.

Lens brightness and image stabilizer

The lens brightness and aperture value is f/4.

The lens is to considered fairly bright.  This will make it so much easier shooting in darker environments where you do not want or can use flash lighting, for example in churches or at different sports venues.

A feature worth commenting, which is also related to lens brightness, is that the brightness and maximum aperture-value remains constant regardless of focal length used. This makes it easier for you as a photographer. No matter if you are have the focus ring and focal length at 17 mm or at 40 mm the aperture value can be f/4.

The lens lacks image stabilization, which otherwise os good for avoiding the blur that can occur when using slow shutter speeds. 

Filter and Lens Hood

The lens has a traditional filter thread on the front and its measuring 77 mm which also the filter you will use must have. If you use for example an UV filter can be a cheap insurance against scratches and dust.

If you buy this lens it will come with a lens hood, whose model name is "EW-83E".

Images of Canon EF 17-40mm F4 L USM

In order to see larger product images of the lens, click the link below.

Things to consider before buying

Below you will find some summarized points and facts that can be considered as the 'pros and cons' of this lens. These are based entirely on the facts and values that are accessible through the lens specification, so we highly recommend that you also read the reported reviews available (see tab 'Reviews'); this in order to get a more complete view of the lens and its capabilities. Reviewer opinions reflect the lens, its use and its optical performance in a more accurate way, but any way - here a few different points to consider before buying this lens.

  • Constant maximum aperture value regardless of focal length
  • Works on all sensor types
  • A lens hood is included
  • The lens is sealed against dust and moisture

Our Review Ratings

Time to grade Canon EF 17-40mm F4 L USM .

Build Quality     
Image Quality     
Autofocus     
Sharpness     
Versatility     
Value     
Overall rating 3 of 5

Best deals on Canon EF 17-40mm F4 L USM

Make sure to check out our price information page for best offers on this lens.