Sony Alpha A9 vs Canon EOS 5D Mark IV – Which is Better?

These two models may be targeted towards slightly different audiences, but a good helping of similarities mean that some users may add both to their shortlist. Here, we take a look at where they mirror each other and where they differ.

Design and ergonomics

As both models are designed with professional users in mind, it comes as no surprise that both make use of magnesium alloy (among other materials) in their construction. Both also offer weather resistance to some degree, although you’ll need to use a lens with similar level of sealing on either camera for complete protection.

The EOS 5D Mark IV is the larger camera of the two, and weighs just over 200g more when loaded with a battery. In terms of physical design the two models stick to a similar idea, each bearing rear control dials and AF-point selection controls, although the A9 has the advantage of a tilting LCD screen.

It’s not as large or as high in resolution (3in and 1.44million dots vs 3.2in and 1.62million dots on the EOS 5D Mark IV) but it does match the EOS 5D Mark IV in offering touch functionality. Above this sits another key difference: a 3.7million-dot electronic viewfinder, in contrast to the EOS 5D Mark IV’s optical alternative.

Sony Alpha A9
Canon EOS 5D Mark IV

Both bodies incorporate two card slots, with Sony opting for a dual-SD setup and Canon offering both CompactFlash and SD-type slots. The EOS 5D Mark IV supports both UDMA7 CF cards and UHS-I-rated SD media, but not UHS-II. The A9 has both UHS-I and II support in one slot and just the former in the other, and you can also use the company’s MemoryStick format in one of the slots if you want. You won’t, but you can.

Image Quality

Each body may sport a full-frame sensor, but there are a number of key differences between these.

The sensor inside the A9 offers 24.2MP and is constructed with a stacked, back-illuminated structure. This architecture includes memory to temporarily store information from the sensor, which in turn helps it achieve faster readout speeds.

The sensor inside the EOS 5D Mark IV, meanwhile, offers a higher 30.4MP but a more conventional design. Like the A9’s sensor, however, it offers phase-detect AF pixels, something we’ll look at later on on.

Sony Alpha A9
Canon EOS 5D Mark IV

The EOS 5D Mark IV’s sensor operates between ISO 100 and 32,000 as standard, with extension settings equivalent to ISO 50 and 102,400 alongside. By comparison, the A9’s range is a fraction broader, with a standard ISO 100-51,200 range and ISO 50- and 204,800-equivalent settings as expansions. Quite how well each performs at their uppermost settings, however, is a different matter.

5-axis image stabilisation is built into the A9’s body, and Sony claims this has a maximum effect of 5 stops. You can also use this in conjunction with an optically stabilised lens, with corrections divided between the two systems.

To benefit from image stabilisation on the EOS 5D Mark IV you need to use a lens with the feature built in. Many of Canon lenses do now have this, although Sony’s system comes out on top for convenience.

Special Features

The EOS 5D Mark IV’s highlight features include Dual Pixel CMOS AF and Dual Pixel Raw, both made possible by phase-detect AF pixels on the main sensor.

The former feature covers 80% of the vertical and horizontal imaging area and allows for smooth changes to focus in live view and while video recording. The latter, meanwhile, lets you adjust the point of best sharpness once the image has been captured among other things.

When shooting conventionally, the EOS 5D Mark IV’s focusing system offers 61 points in total, covering an “expanded” area of the frame, with 41 of these being cross type. Sensitivity is rated down to -3EV at the central point and -4EV when using live view, while burst shooting happens at a maximum 7fps.

Sony Alpha A9
Canon EOS 5D Mark IV

So how does the A9 compare to all this? Well, it offers 693 phase-detect AF points covering 93% of the frame, and 25 contrast-detect AF points, with sensitivity rated down to -3EV. Through the use of an electronic shutter – it offers both mechanical and electronic shutters – it can fire at 20fps with AF and AE throughout, and this also allows it to offer blackout-free shooting, together with silent shooting and shutter speeds as high as 1/32,000sec.

Both the EOS 5D Mark IV and Alpha A9 are primed with Wi-Fi and NFC, although Canon goes one further by also throwing in a GPS system. The EOS 5D Mark IV’s battery life is also more impressive, with around 900 shots per charge versus the A9’s 650 with the LCD screen (and just 480 with the viewfinder), although both bodies can be used with optional battery grips should the user want to do so.

Video Quality

While both cameras are capable of 4K video recording, each company has approached it quite differently.

The EOS 5D Mark IV, for example, records in DCI 4K (4096 x 2160 pixels), while Sony has opted for the more common UHD 4K (3840 x 2160 pixels) format for the Alpha A9.

Sony Alpha A9
Canon EOS 5D Mark IV

Canon has also decided to use Motion JPEG compression for its 4K footage. This isn’t the most efficient format and does mean file sizes are fairly hefty, although it should allow for better-quality image grabs. Sony, meanwhile, opts for the XAVC S format for 4K recording.

The EOS 5D Mark IV also applies a crop factor of 1.64x to 4K footage, while the Alpha A9 only applies a 1.24x crop factor when shooting at 30p. Otherwise, it uses the full width of the sensor, which makes getting wide angles easier.


The Alpha A9 generated a lot of excitement when it was announced a few weeks ago, and rightly so. Its AF system and burst rate alone scooped up plenty of attention, but with the upgraded viewfinder, new full-frame sensor, 4K video and built-in image stabilisation on top of this, it proved itself to be a compelling proposition.

So what’s not to like? Pretty much the same thing that puts many people off with new Sony releases: price. The EOS 5D Mark IV is hardly a cheap camera, but the Alpha A9 certainly makes it appear more affordable.

Add to that a 30.4MP sensor, far wider selection of native lenses, better battery life, a top-plate LCD, built-in GPS system and, to a lesser extent, its clever Dual Pixel Raw feature, it still holds plenty of appeal for either DSLR users or anyone else after something a little more traditional.