Canon's new speed champion posts impressive results in our full lab test.
In our field tests, the autofocus was equally impressive, quickly finding and tracking moving targets -- racing taxicabs, zoo creatures, wild birds, and more -- under various lighting conditions in just about every situation we faced. There's been some online chatter about flaws and failures of the autofocusing system on the Mark III, but we did not experience any of these problems in our field tests with a variety of Canon and third-party lenses, regardless of the autofocusing method. Whether we tried shutter-button focus, AF-button focus, single-focusing point focus, or expanded focusing point focus, the AF speed and tracking worked equally well and quickly found our subjects in bright light and low light.
A VERY BIG LCD FOR A PRO DSLR -- WITH A TWIST
The Canon EOS 1D Mark III packs a 3-inch ultra-wide viewing angle 230,000 pixel LCD on the back, which is quite big for a pro-level DLSR. The smudge- and scratch-proof coating does a good job protecting image display, and the tough coating over the LCD barely yields to a forcefully applied thumb right to the center. It'll take a special effort to bang up this LCD. It's big, but it appears tough enough for the abuses of all but the most hardcore gear-destroying pros.
Contrast on the display is crisp and sharp, and the combination of the larger LCD and joystick-based navigation make for a much easier set-up and review experience. Magnified Image jump (up to 10x magnification) linked to the active focal point during playback is a great feature for quickly separating the selects from the outtakes in-camera.
On the Mark III, the LCD isn't just for inputting shooting settings and image review. Like a pocket digicam, the LCD can be used for a real-time live image preview. In this mode, the optical viewfinder is useless, as the reflex mirror is locked up, but the LCD screen displays exactly what you'd see through the lens, with the added benefits of metering emulation and white balancing to check for exposure problems and unwanted color-casts.
When we say "exactly what you'd see through the lens," we mean it. Unless the Depth of Field preview button is depressed, the on-screen display shows maximum aperture with the shallow depth of field that entails. But press the DOF preview button and the image quickly shifts to display your stopped-down preview and the LCD gains up quickly. Auto White balance preview also adjusts quickly and dead-on to shifting lighting conditions.
With the Mark III tethered to a computer, the Live Preview mode can also be displayed on your monitor. This could come in handy for studio shooters wanting to give a real-time preview to a client or to the creative sports photographer setting up a remote camera at an obtuse angle.
Photojournalists with a wide-angle lens set to hyperfocal and stopped down a bit to f/8 will love the advantage of the live view mode as they hold up their camera statue-of-liberty style, hoping for a usable Hail Mary shot.
The lack of autofocus makes moving-subject macro work more challenging than useful, but for still subjects or set-up shots, and high- or low-angle shots, this feature borrowed from point-and-shoots certainly has its uses in a pro-level camera.
It's a major advancement, and Live Preview certainly will gain its adherents, but it's not perfect -- yet. Always-on Depth of Field preview and autofocusing (especially via a tethered computer) will really make Live Preview a much more robust shooting experience.