Please see the 17mm comparison page for details.
Mouse over the image below to compare. Both zooms show faint pincushion distortion (bowing inwards), typical for a zoom lens at its long end. But it is so low it can be ignore.
The 17/4L shows the lowest distortion and the most natural looking image.
The 17-40/4L has strong barrel distortion at 17mm, with the 16-35/2.8L II showing somewhat less of it, but both zooms look positively stretched compared to the 17/4L.
Article continues for subscribers...
If you’re already a subscriber, CLICK HERE TO LOG IN
diglloyd Advanced Photography includes hundreds of pages of exclusive coverage and high resolution, Retina-grade example pictures detailing Canon and Nikon DSLR bodies and their lenses, with in-depth analysis of sharpness and contrast, color, bokeh, vignetting, distortion, MTF, and flare. Also included is a wealth of in-context technique and workflow insight. Since 2006, diglloyd Advanced Photography is the authoritative review and on-line reference for discerning Canon and Nikon shooters. Subscriptions cost $ per year.