I’ve borrowed the new ultra wide angle 114° Canon EF 14mm f/2.8L II from a friend of mine for an in-depth review. Watch this blog for more information. My preliminary impression of the new 14mm is that of a high quality lens with excellent correction for chromatic errors (color fringing). However, I am seeing certain imaging characteristics which have raised some questions I will be looking into. I do hope that the 21.1-megapixel EOS 1Ds Mark III is available soon to make that analysis easier.
Below is a reality check for anyone who thinks that stopping down, even at 14mm, is adequate to exploit today’s high-resolution digital sensors (or that sloppy focusing can be overcome by stopping down). Even at these smaller sizes the inadequate depth of field should be “clear”. Click on images below to see larger versions.
Canon EOS 1D Mark III + 14mm f/2.8L II @ f/5.6
Not persuaded because the image above was made at only f/5.6? The image below was made at f/11, which offers twice the depth of field as at f/5.6, yet is clearly inadequate to render the background sharply.
Canon EOS 1D Mark III + 14mm f/2.8L II @ f/11
Stopping down to f/16 would degrade the image contrast noticeably (due to diffraction) and yet offer only minor improvement with this image. Stopping down to f/22 is out of the question; contrast and resolution would drop unacceptably. So in reality f/16 is the hard limit on the 10.1-megapixel 1.3X-sensor EOS 1D Mark III, with f/11 the last acceptable aperture for near-optimal quality. These numbers are even more restricted on cameras with smaller photosites like the EOS 40D; they become f/8 and f/11 respectively.