Performance and Autofocus

The EOS 5D Mark IV's autofocus system had no problem keeping up with an excited (and erratically moving) pup at the park. Processed to taste from Raw. Canon EF 70-200mm F2.8L IS II @ 200mm. ISO 100, 1/1000 sec, F2.8.

Photo by Carey Rose

The 5D-series has come an awfully long way with regards to performance and autofocus. When the original 5D came out, it had 9 autofocus points (of which only one was cross-type), while the existing 1D-series cameras had a total of 45 points. It would also only shoot at 3 frames per second maximum, which most will agree is insufficient for many sports shooters. With the current autofocus system and 7 fps burst shooting, the 5D Mark IV is easily capable of being a photographers' only camera, so long as he or she doesn't need the insane burst rate or buffer of the 1D X Mark II.

Overall performance

As is typical of modern DSLRs, the 5D Mark IV is speedy in operation with only a couple of minor exceptions. It powers on basically instantly, responds to your inputs as fast as you can twiddle the control dials, and menu navigation and playback are both fluid affairs, whether you use the touchscreen or not. Couple this with a very responsive touchscreen interface for both Live View stills and video shooting, and the 5D Mark IV offers you as well-rounded an experience for more 'traditional' DSLR shooters as it does for those tempted by the increased Live View performance.

Unfortunately, the 5D Mark IV makes do with conventional CompactFlash and SecureDigital slots, rather than anything faster like the CFast 2.0 slot in the 1D X Mark II. Even with the fastest cards you can buy, some users will likely wish for a larger buffer when shooting at 7 fps. You'll also need nearly the fastest CF and SD cards you can buy if you plan on there being any 4K video shooting in your future.

Of course, for casual shooting, 7fps is more than enough much of the time. Straight-out-of-camera JPEG with the Canon EF 40mm F2.8. ISO 160, 1/160 sec, F5.6.

Photo by Carey Rose

Continuous shooting performance measured

Here's how the burst shooting looks with a 32GB Lexar Professional 1066x UDMA7 CF card, and a 64GB SanDisk Extreme PRO UHS-I U3 SDXC card. These were all shot at 1/500 sec at ISO 100.

Quality Burst rate Buffer depth
Raw + Large fine JPEG on CF 7 fps ~20 shots
Raw + Large fine JPEG on SD 7 fps ~18 shots
Raw only on CF 7 fps ~33 shots
Raw only on SD 7 fps ~28 shots
Raw + Large fine to both 7 fps ~16 shots
Large fine JPEG on either

7 fps

Unlimited

Now, figures like that are likely to be perfectly acceptable for most general shooting, including events, weddings, and even some action sports - and if you're primarily a JPEG shooter, you're in the clear.

But for those dedicated to shooting long bursts of both Raw and JPEG files, you may hit that buffer sooner than you'd expect (we certainly did with our bike tests - more on the next page). In addition, you're going to have to wait for the buffer to clear for a few seconds before you can check your images. 

One last important note - shooting at higher ISOs does result in a 20-30% reduction in those figures. So, if you're, say, shooting indoor sports at ISO 6400, you'll get around 15 Raw+JPEG images onto a CF card, and about 13 onto an SD card. This serves to further reinforce the fact that if you need good burst performance, particularly in less-than-ideal lighting conditions, you may want to consider stepping up to the 1D X series.

Overall autofocus

The EOS 5D Mark IV inherits a very similar autofocus system to its big brother, the EOS-1D X Mark II, which is itself very similar to the older 1D X  Mark I and 5D Mark III. Compared to those older models, there's greater vertical spread of its 61 points. 41 of these are cross-type, and there's a center point that is sensitive down to -3 EV. The center five points, arranged vertically, are dual cross-type and promise even higher precision with lenses faster than F2.8. One differentiator, though, is that the 1D X II uses a 300k-pixel RGB+IR metering sensor to aid in subject tracking through the viewfinder, while the 5D Mark IV makes do with a sensor that has half that resolution.

Like the 1D X Mark II, the autofocus system on the 5D Mark IV is complex and takes some time and experience to learn its ins-and-outs. In other words, if you find that you're not satisfied with your number of in-focus 'keepers,' you may need to experiment with different AF case and AF area modes until you find that sweet spot. Once you put in that effort though, you'll find that the system will cope with just about any photographic situation you might find yourself in.

While its older Mark I and Mark II brethren would often give up in dim lighting conditions, the Mark IV will reliably lock focus and offer up great image quality to boot. Processed to taste in-camera from Raw. Canon EF 40mm F2.8. ISO 6400, 1/125 sec, F2.8.

Photo by Carey Rose

Significantly, the 5D Mark IV is the first full-frame Canon DSLR to be able to shoot continuously while using Live View servo autofocus (the APS-C Canon EOS 80D does this as well). Though the camera will slow its burst rate to a maximum of 4.3 fps in this mode, it works very well, is quite accurate and can be handy for allowing the camera to track a subject with a little less input from the user. We found the 5D Mark IV's subject tracking in Live View to be even 'stickier' than using Canon's Intelligent Tracking and Recognition (iTR) through the optical viewfinder, and since its reading focus directly off the image sensor, shooting with wide-aperture lenses still yields consistent focus accuracy.

Autofocus presets

As is typical of recent high-end Canon DSLRs, the 5D Mark IV has six preset 'case modes' to help you make the most of the autofocus system. It's a simpler approach than asking users to manually dial in values for tracking sensitivity, acceleration and deceleration tracking and AF point auto switching, and we've seen how even small adjustments to any of these presets can have a meaningful impact on how the camera behaves with respect to moving subjects.

Autofocus point selection

Autofocus speed and accuracy were among the top of users' requests during Canon's 5D Mark IV market research, and the camera doesn't disappoint. I ended up overexposing this scene because I didn't have the time to change settings, but the autofocus locked on the plane swiftly and easily. Processed to taste using a beta version of Adobe Camera Raw. Canon EF 24-70mm F2.8L II USM @ 65mm. ISO 100, 1/500 sec, F5.6.

Photo by Carey Rose

Also typical of Canon DSLRs is the selection of autofocus area modes, which are designed to further allow you to tailor the camera's autofocus behavior to your subjects.

  • Single-point Spot AF allows you to manually select a single point, which will only focus based on a very narrow area. It's great for pinpoint accuracy, such as a subject's eye, even through something like a motorcycle helmet, or a small bird surrounded by branches. It is not recommended for moving subjects.
  • Single-point AF functions identically to the previous mode, but with a less narrow area. It's more suitable for focusing on still life or an eye during traditional portraiture (Single AF), or continuously focusing (AI Servo) on a subject that is easy for you to follow. This is the default mode of focusing.
  • AF Point Expansion works with either four or eight additional autofocus points surrounding the point you've manually chosen. This is an ideal mode for shooting sports - if you accidentally let your chosen AF point slip off your subject, the camera will (depending on the case you've chosen) attempt to use the additional four or eight 'helper' points to intelligently determine whether you wish to keep focus on that subject, or re-focus onto a new subject. It's most suited for moving subjects in AI Servo, as the system can get distracted for still life or portraiture in Single AF - it might not acquire focus exactly on a subject's eye, for example.
  • Zone AF divides the camera's 61 autofocus points into nine zones which are user-selectable, and is again meant for continuous focusing on moving subjects. According to Canon, it's useful for larger subjects or subjects moving over a larger area, as the camera decides where to focus within that chosen zone. It's not great for situations where obstacles might block your subject.
  • 61-point Automatic Selection AF works as you might guess - it lets the camera do the work. In Single AF, it will automatically select an AF point(s) for you, based on information from both the AF module and the metering sensor. In AI Servo, it'll do the same, but use those same two modules to intelligently shift the AF point(s) to stick to your subject as it moves (and the system will give priority to faces if you have this option enabled in the menus). Changing a menu option allows you to specify the initial subject yourself by selecting an AF point and placing it over that subject before initiating focus. This is most similar in practice to Nikon's 3D Tracking in that it allows you to constantly reframe your composition without having to move the autofocus points or follow the action manually.

Now with the system overview out of the way, let's take a look at how depth-tracking and iTR tracking worked through the viewfinder, as well as how Dual Pixel AF copes with tracking and moving subjects in Live View.