Canon EF 200-400mm f/4L IS USM Extender 1.4x Quick Review
Studio Tests (Full frame)
The 200-400mm is perhaps most likely to be found on high-end full frame camera such as the EOS-1D X and the EOS 5D Mark III. Test results on full frame are little short of extraordinary - the lens comes ridiculously close to matching Canon's very best primes. Click for comparisons with the EF 300mm f/2.8L IS II USM and EF 400mm f/2.8L IS II USM in our lens widget.
|Sharpness||Sharpness results are remarkable - the lens delivers superb results right across the frame wide open at F4, all across the zoom range. There's essentially no need to stop down for sharpness - there's little difference from F4 through to F11.|
|Chromatic Aberration||Chromatic aberration is very low. If you look really hard you may see a little fringing at each end of the zoom, but is simply won't be a problem in normal use.|
|Vignetting||Vignetting is on the whole pretty low. It may possibly be visible in some situations towards the long end of the zoom.|
|Distortion||Distortion is essentially nonexistent at any focal length.|