Canon EOS-1D Mark III

Manual Control Options
The EOS-1D Mark III is a fully manual camera, with a range of options to take full control of exposure and image parameters, or to modify the values set by its automated modes.

Focus
Auto Focus
The EOS-1D Mark III has 45 autofocus sites, and 18 of them are cross-type with f/2.8 or faster lenses. The center site is cross-type down to f/4.0, and all of the sites work with lenses as slow as f/5.6. The sites are arrayed in an oval that covers about the central 2/3 of the frame. Canon notes that the cross sensors reach further to the edges of the frame than the ones on the Mark II cameras, which have only 7 cross sensors. Without having the cameras side-by-side, we can't be sure if Canon has caught up to Nikon in dispersing sensors widely across the frame.

The Mark III's system was fast and accurate in low light, with a fast lens mounted. Our full review will be more specific regarding focus performance. The Mark III can be set to either one-shot autofocus or Predictive AI Servo AF, the continuous mode used for tracking subjects in motion.

Manual Focus
Manual focus in the optical viewfinder is aided by a bright, contrasty screen. The EOS-1D Mark III's most surprising feature, its live preview, requires manual focus. Because it allows the user to magnify any portion of the frame either 5x or 10x, it allows critical focus on any portion of the frame. It works well and probably offers more accurate manual focus than the optical viewfinder, when the camera is on a tripod. The live preview refreshes 30 times a second, which is plenty for a full-frame display, but at 10x, some smearing is apparent when the camera is in wobbly hands. We tried it with a 50mm lens.

We used live preview with the default settings and look forward to tweaking it for better effect in our full review. For general use, live preview isn't going to be used often enough to devote the SET button to activating it – especially when accidentally bumping the button blacks out the viewfinder. It's also unfortunate that hitting the menu button defeats live preview. If a user checks a menu setting while live preview is active, when they switch back from menu to shooting, live preview is turned off. We didn't have time to dig through the menus to see if that quirk could be switched off, but it's annoying.

Exposure
The EOS-1D Mark III can set exposure compensation 3 stops above or below the metered reading in either 1/3 or 1/2-EV increments. Compensation works in program, aperture priority, or shutter priority modes. The Mark III can also be set manually, with a scale showing how closely the manual setting fits the meter reading.

The Mark III can be set to bracket exposures over the same range that exposure compensation can be set and can be set to vary aperture or shutter speed or to use the program mode to choose the parameter to vary.

Metering
A 63-zone metering array gathers data for evaluative metering on the EOS-1D Mark III. The Mark III also offers spot, center-weighted and Canon's unusual “limited area” metering, which is essentially a very large spot, at about 13 percent of the frame. The spot meter can be set to overlap the active autofocus site. It meters about 3 percent of the frame. We look forward to testing the Mark III's exposure performance. We could not form a judgment based on our first look at PMA.

When the Mark III is in live preview, it uses data from the CMOS imaging chip to meter exposure and offers live RGB histograms. Our full review will examine how live meter readings compare with the dedicated metering array.

White Balance
Canon has long offered flexible and easy-to-use white balance control. The EOS-1D Mark III has an automatic setting, direct Kelvin entry with a scale from 2500K to 10,000K, manual white balance, with room to save 5 measurements, and presets for sun, shade, overcast, tungsten, fluorescent and flash. White balance can be altered on blue-amber and green-magenta axes and can be bracketed.

The auto setting did not perform well in the truly odd lighting at PMA. Overall lighting was mercury vapor, augmented with tungsten, and a constantly varying mixture of red, green and blue LEDs, so it was far from a fair test. Our full review will provide much more reliable results.

White balance is accessed by hitting the Function button a few times. It would be better if white balance had a dedicated button, instead of Picture Styles.

ISO
Not counting its extended settings, the EOS-1D Mark III has an ISO range of 100 to 3200. The extended range indicates Low, which is ISO 50, and High, which is 6400. The Mark III we examined was set for 1/3-EV increments but that's customizable. The ISO button is near the shutter release, and the setting shows up in the viewfinder, so users can set it without taking the camera down from shooting position. In marginal conditions, with firmware that's “not final,” images shot at 3200 and H looked good enough to be interesting.

The Mark III's “Safety Shift” feature can adjust ISO, so that exposures remain within customizable bounds.

Shutter Speed
The EOS-1D Mark III can time exposures from 1/8000 to 30 seconds, in increments of 1/3 EV. It also has a Bulb setting for time exposures. In Bulb, the top LCD displays elapsed time. With dedicated flashes, the shutter can sync at up to 1/300 of a second. With others, it tops out at 1/250. The shutter speed range is typical of DSLRs and indicates a practical limit on timing for image quality.

Aperture
The EOS-1D Mark III controls the aperture of EF-mount lenses electronically, allowing adjustment in increments as small as 1/3-EV. Canon's line of lenses is the most extensive among DSLR manufacturers. Canon's better lenses are the L series. Arguments about whether anyone else's optics are better than L lenses amount to splitting hairs - they're capable of excellent performance.

Modes	Page 7 of 12		Image Parameters
Canon EOS-1D Mark III First Impressions Review Navigation
Intro	Testing/Performance Expectations	Physical Tour	Components
Design/Layout	Modes	Control Options	Image Parameters
Connectivity/Extras	Overall Impressions	Conclusion	Specs