Camera Test: Canon EOS 5D Mark III DSLR

How does the Canon 5D Mark III stack up against its competition the Nikon D800? Check out our in-depth comparison in the Buying Guide.

There’s no questioning the popularity of Canon’s EOS 5D Mark II. After all, it’s a very close second to Apple’s iPhone 4 for the most-used camera on the image-sharing website Flickr. And now Canon has brought us the EOS 5D Mark III. If our tests are a guide, get ready for an even bigger hit.

The pixel count hasn’t gone up much­—a mere 1.2MP bump from the Mark II’s 21.1MP. But look deeper and you’ll see new metering and autofocus systems, an increase to 6 fps bursts (from 3.9), a top sensitivity of ISO 102,400 (up from ISO 25,600), plus several other convenient new features.

After running it through the Popular Photography Test Lab and experiencing it in the field, we can say that the 5D Mark III ($3,500, street, body only) is every bit the imaging machine the Mark II was—and more. It delivers low-noise, high-resolution images with manageable file sizes.

In the Test Lab
A perfect blend of accurate color rendering, high resolving power, and low noise comes together to earn Canon’s EOS 5D Mark III an Excellent rating in overall image quality from ISO 50 all the way through ISO 12,800.

Let’s pause for just a moment to realize what that means: The Mark III delivers color images with a Low noise rating on our stringent scale up to a sensitivity beyond that which was, not too long ago, relegated to very coarse-grained black-and-white film. That’s a seriously admirable achievement.

Despite the Mark III having about one-third fewer pixels than the Nikon D800, it still easily scored an Excellent rating in our resolution test, with 2750 lines per picture height at its lowest (expanded) sensitivity of ISO 50. While that’s a little less than the 2830 lines than the 5D Mark II delivered in this test, given the Mark III’s noise performance (and considering that it has enough resolution for the vast majority of photographers), we don’t see this as a real problem.

Likewise, the Mark III’s average Delta E at ISO 50, our measure for color accuracy, was 6.9 compared to the Mark II’s slightly better score of 6.3. Still, both earned an Excellent rating in this test, and we doubt that anyone will be able to see a difference between the accuracy of their color reproduction.

Looking for clean images in very low light? Welcome to Mark III country. The camera earned an Extremely Low rating from ISO 50 through 400, stepping up to Very Low from ISO 800 through 3200, and Low at ISO 6400 and 12,800. It doesn’t become Unacceptable, and then only barely so, at ISO 51,200. Even at ISO 102,400, the noise score is only 4.4—compared with 4.9 at ISO 25,600 on the Mark II.

But this noise performance is thanks in part to a heavy dose of noise reduction at higher ISOs—which comes at the price of resolution. At ISO 12,800, the Mark III showed 2520 lines of resolution, but it dropped signicantly to 2150 lines at ISO 25,600. By ISO 51,200 it hit 1910 lines, and at ISO 102,400 it resolved just 1500 lines.

To compare, the Nikon D800 reaches Unacceptable noise at ISO 6400, yet still manages to resolve 2900 lines. Prior to the D800, the full-frame DSLR with the most resolution was Sony’s Alpha 900, which resolved 2440 lines at its top of ISO 6400, though it too had Unacceptable noise at that setting.

In our lab-based autofocus-speed test, the Mark III showed very pleasing—if not record-breaking—results. It was able to focus in less than a second all the way down to nighttime darkness (EV –1). That’s impressive. At EV –2, it became considerably less consistent, but averaged 1.15 seconds. So while it’s not the fastest focuser we’ve seen, it represents a massive improvement over the Mark II: In the bright light of EV 12, the latter took 0.51 sec to focus, while the Mark III took 0.37 sec. Worse still, at EV –1 the Mark II lagged nearly a half-second behind, taking 1.47 sec to lock focus and shoot an image.

In the Field
Though it’s about the same size as its predecessor, the 5D Mark III’s body has some advantages. The grip is more comfortable, with a nice divot for your fingertips on the side facing the lens. And the rubber has a different texture for more friction, so the grip feels more secure.

The well-placed, dedicated live view/video switch and button sit just to the right of the finder, making entering and exiting those modes intuitive and speedy. The on/off switch is now on top with the mode dial, and the second command wheel on the back now has a dedicated lock switch. This should make it less confusing to lock and unlock the wheel, and eliminates the possibility of accidentally turning off the camera when locking it, as could happen on the Mark II.

The addition of the Quick menu lets you change settings rapidly through the LCD interface when setting up for a shoot.

If you prefer to use dedicated buttons to change settings, the Mark III has you covered with a slew of them. Many let you change two settings through the different command wheels. There’s a programmable multifunction button just behind the shutter button; the depth-of-field preview button on the front of the camera, like many of the buttons on the 5D Mark III, can be assigned one of numerous functions should you want to customize the camera controls.

Betraying its age, the 5D Mark II had only one memory-card slot (for CompactFlash), while the Mark III has both a CF and an SD card slot. These can be configured to mirror one another, or to fill up in sequence, or to split different kinds of files between them—you can record RAW to one and JPEG to another, for instance.