Canon 5D Mark III Technical Info

By Mike Tomkins


The 5D Mark III's 22.3 megapixel, full-frame CMOS image sensor has a pixel pitch of 6.25 microns. Although resolution is almost unchanged, it now features eight-channel readout, gapless microlenses, and boasts improvements in transistor structure and on-chip noise reduction that should yield improved image quality, even for raw shooters.

Two reduced-resolution raw modes are also available, providing 10.5 or 5.5 megapixel resolution.

Sensitivity ordinarily ranges from ISO 100 to 25,600 equivalents, and can be expanded to encompass ISO 50 to 102,400 equivalents. For video mode, the upper limit is capped at ISO 25,600 equivalent.

Canon's DIGIC 5+ processor first appeared in the 1D X. Although the 5D Mark III uses only a single processor, Canon says it's 17 times more powerful than the Mark II's DIGIC 4 chip.

As well as enabling faster 6 fps burst shooting, there's also more power for noise reduction, and Canon is predicting a two-stop improvement for JPEG shooting. The greater performance is also used to add real-time chromatic aberration correction for both still and movie shooting.

The Mark III's 61-point autofocus sensor is also borrowed from the EOS 1D X. As in that camera, there are 41 cross-type points, of which 20 work to f/4.0, and 21 are f/5.6 capable. Of the latter, five will work as high-precision points to f/2.8. The remaining points are horizontal line-types, sensitive to f/5.6.

Also new since the 5D Mark II is Canon's AI Servo III, which is quicker to start tracking your subject, and should handle momentary obstructions between camera and subject more gracefully.

The 5D Mark III's 63-zone dual-layer iFCL metering sensor was first seen in the EOS 7D. The top layer is sensitive to red and green, while the bottom layer detects blue and green. This full-color metering allows better subject detection, information which is also fed back to the autofocus system to further aid subject tracking.

As well as evaluative, partial, and center-weighted, there's also a tighter 1.5% spot metering mode.

Like its predecessor, the 5D Mark III has a Canon EF lens mount, and doesn't accept sub-frame EF-S lenses. Thanks to its full-frame sensor, there's no focal length crop.

The shutter mechanism is rated as good for 150,000 shots, unchanged from the 5D Mark II. A 'Silent' shooting mode reduces operation noise, but reduces burst-shooting speed to three frames per second.

The 5D Mark III's viewfinder now has 100% coverage, slightly upgraded from 98% in the previous model. As in the EOS 7D, there's an on-demand grid function, and you can also display the locations of the 61 focusing points.

Like the 1D X, there's a 3.2-inch Clear View II LCD panel with a high resolution of approximately 1,040,000 dots.

Of course, there's still a monochrome status display on the top deck, as well.

The EOS 5D Mark III's video functionality is similar to that of the 1D X, but with an important addition: a headphone jack for audio monitoring, useful given the ability to adjust audio levels during recording. (You can also adjust ISO sensitivity, shutter speed, and aperture as the video is captured.)

As well as 1080p 24/25/30 fps and VGA 25/30 fps, there's now a 720p 50/60 fps mode. The 4GB recording limit is gone, and you can save clips as long as 29 minutes, 59 seconds in all resolutions. Compression choices are ALL-I intraframe or IPB interframe, with embedded free-run or rec-run timecode. Canon says that video moire has been greatly reduced since the 5D Mark II.

As well as the previously-mentioned microphone and headphone jacks, the 5D Mark III also offers up a PC sync terminal, combined standard-def AV output / USB 2.0 High Speed port, wired remote control port, and high-def HDMI video output.

Dual card slots mean that the 5D Mark III can now record to either UDMA 7 CompactFlash or Secure Digital cards, including SDHC and SDXC. Interestingly, as well as using the secondary card as an overflow or duplicate, or to segregate by file type, you can also record different raw or JPEG types to each card. For example, you could save full-res raw files on one card, and reduced-res raw files on the other.

The 5D Mark III takes the same LP-E6 battery pack as the 5D Mark II, letting you save a little money if you're planning on upgrading from the older model, but have a stack of batteries on hand.

Battery life is rated to CIPA testing standards at 950 shots with the viewfinder, or 200 shots in live view mode, at 73°F / 23°C. This can be approximately doubled by shooting with two packs, using the BG-E11 battery grip.

Although the target market is clearly experienced photographers, the 5D Mark III caters to the occasional time when you want to lend your camera to a less-experienced photographer, perhaps to get in the shot yourself. The Full Auto mode has been upgraded, and Canon says it will now do a better job of recognizing the appropriate scene type.

The Mode dial has a central locking button, as seen on the 60D. (This was also available as an option on the 7D and 5D Mark II, but here it's the default.)

A new Rate button to the left of the LCD provides instant access to image rating functionality, letting you assign anywhere from one to five stars for each image. The 5D Mark III also adopts Canon's Q button, just to the right of the LCD, for quick-control functions.

On the top deck, you can now assign the Multi-Function button to instantly switch between raw and JPEG shooting with a single press.

The EOS 5D Mark III's body includes weather-sealing to a level said to be better than that of the 5D Mark II, but not to the same degree as an EOS 1-series body like the EOS-1D X.

There are quite a few significant changes to the 5D Mark III's firmware, as well. For the first time in an EOS model other than the 1-series, the 5D Mark III can now capture 2, 3, 5, or 7 shots in a bracketed sequence. This will be particularly useful to fans of HDR photography, and if you don't want to deal with processing HDR images yourself, there's also an in-camera three-shot HDR mode, a first for an EOS model. Four different processing effects are available. You can also opt to have the source images saved along with the HDR shot, so if you're not satisfied with the result achieved in-camera, you can reprocess the HDR on your computer.

The 5D Mark III also offers up a multiple exposure function. Just like the 1D X, you can combine up to nine frames into a single exposure in-camera. There's also a dual-axis level display, similar to that of the EOS 7D.

In Playback mode, you can now process raw images in-camera, and take advantage of the lens correction functions when doing so. Among the user requests that Canon has heard and answered with the 5D Mark III, there's now a side-by-side comparative playback display (including synced magnification and a histogram function), plus the ability to manually set the first four characters of image file names.

Alongside the 5D Mark III, Canon has launched a new flagship flash strobe. The Speedlite 600EX-RT allows not only the line-of-sight optical wireless functionality of existing units, but also a new two-way radio connectivity, with 30 meters / 98.4 feet range. Remote camera triggering is possible from a flash strobe. 15 radio channels are available (plus auto), and up to 15 Speedlite flashes can be used on a channel, in as many as five groups, with each group separately able to be set to E-TTL or controlled manually. A 4-digit wireless radio ID can be assigned to separate radio networks.

The 600EX-RT has a guide number of 60 meters / 197 feet at maximum zoom, and has a zoom range of 20 to 200mm. It also has a more rugged shoe mount, and ships with a gel filter holder and tungsten / fluorescent filters.

There's also a new ST-E3-RT transmitter, similar to the existing ST-E2, but with support for the new two-way radio system.

The 5D Mark III uses a new BG-E11 battery grip, which includes a duplicate multi-controller for portrait shooting.

There's a new WFT-E7A wireless file transmitter that also supports the EOS 7D and 60D, and includes 802.11a/b/g/n Wi-Fi and gigabit Ethernet.

An external GP-E2 GPS receiver connects to the camera via USB, and mounts on the hotshoe or off-camera. As well as recording latitude, longitude, altitude, and UTC time in the EXIF header of images, it has a compass function, and can capture GPS track logs.