Sony a7RIII vs Canon 5D MkIV – Which One Should You Buy?

Sony shocked the photo industry when it announced its latest version of the a7R – the a7RIII. The mirrorless camera has built upon the success of its predecessor and brought fast shooting speeds and enhanced focus to the a7R line-up. However, the Canon 5D MkIV, the latest model in the legendary 5D line-up, also offers photographers a huge amount of features and boasts rich heritage. So, let’s take a closer look at the spec sheets to discover which of these two big-hitting cameras is worth your money and right for your sort of photography…


The Sony a7RIII is a mirrorless camera, built around a full-frame sensor that offer an incredibly high resolution of 42-megapixels. The weather-sealed body can be used in harsh environments and makes use of Sony’s E-Mount for its lenses. The Canon 5D MkIV on the other hand is a DSLR and is built around a full-frame CMOS sensor that offers 30-megapixels, so it clearly loses out to the Sony in terms of resolution, although 30-megapixels should be plenty for most professional photographers.

The weather-sealed 5D MkIV uses Canon’s tried and tested EF lens mount, meaning there’s a much bigger range of optics available than for the Sony from Canon themselves and from third-party lens manufacturers such as Sigma and Tamron. On the rear of the a7RIII, you’ll find a 3-inch tilting screen with a resolution of 1440K-dot and having this ability to tilt will make it easier for photographers when it comes time to compose awkward angles or when shooting video. The screen on the Canon 5D MkIV is fixed, but it is both larger (3.2-inches) and boasts a higher resolution (1630K-dot). Both cameras feature dual storage slots, with the Sony featuring two SD cards and the Canon featuring one SD and one CF card. By including both media types, the 5D MkIV will mean that photographers using the predecessor camera (the 5D MkIII) will still be able to make use of all their memory cards as it too uses the SD/CF ratio. It’s good news that the a7RIII and 5D MkIV feature dual card slots as it’s an essential feature for today’s professional photographers.

One area where the cameras do differ is viewfinders; while the Canon features a traditional optical viewfinder, the Sony features a high-resolution 3686k-dot Electronic Viewfinder (EVF) instead. Another physical difference is the size and weight specs; as you’d expect from a camera with a mirrorless design, the Sony is more compact and weighs in at 657g compared to the heavier 5D MkIV at 890g.

Both cameras feature touch-sensitive LCDs, but the Sony’s boasts a tilting design.


Both cameras feature impressive autofocus systems, with the Canon 5D MkIV sporting 61-AF points, 21 of which are the sensitive cross-type. What’s more, the 5D MkIV also benefits from Canon’s Dual Pixel AF technology to lock onto subjects quickly. The Sony however breaks new ground with its sophisticated AF system and sports 425 contrast detection AF points, up from 25 on the older Sony a7RII. This incredibly leap forward on focusing ability enhances the a7RIII’s ability to focus over a wider area of the frame, stacking the odds of capturing a sharp image further in the photographer’s favour.

Another performance area where the a7RIII comes out on top is burst rate. The older a7RII could only shoot 5 frames per second (FPS), but the newer a7RIII doubles that figure to 10 FPS and this pulls ahead of the Canon 5D MkIV, which can shoot 7FPS. While 7 frames per second is still an impressive figure, if the majority of photography you capture is motion-based (such as wildlife or sports photography), those extra three frames every second will make a difference.

One performance area where the Canon strikes back is battery life. Although the Sony a7RIII now offers a more respectable 650 shots per charge, the 5D MkIV trumps this figure by enabling photographers to fire off 900 charges per charge. This is an important feature because if you are shooting on locations that are far from recharging points, you don’t want to run out of power just as you are about to capture that perfect image.

Both models feature dual card slots, an essential feature for pro cameras.


Both these cameras offer excellent features that will turn the heads of videographers and make the 5D MkIV and a7RIII tempting options for those earning a living by making video. Both cameras shoot ultra high-quality 4K footage at 30p, with the 5D MkIV’s file a tiny bit larger than the a7RIII’s (4096 x 2160 compared to 3840 x 2160). What’s more, the cameras also shoot Full HD at fast frame rates (120p) which can be used to capture dramatic slow motion sequences.

As you’d expect from cameras designed to appeal to pro and semi-pro videographers, the a7RIII and the 5D MkIV both feature ports for headphones and an external microphone. This will allow users to not only monitor sound, but to also attach that external mic which will deliver far superior audio than any built-in version. One advantage Sony shooter have over their Canon counterparts is that the a7RIII features Sony’s S-Log2, S-Log 3 and HLG (Hybrid Log-Gamma) picture profiles. Canon users can add the brand’s C-log profile to the camera, but this costs extra and must be done at a service centre.

The Canon does strike back by offering a 4K photo mode, which enables users to extract 8-megapixel JPEGs from footage – incredibly useful when you’re trying to capture split-second moments, such as a water drop falling onto a surface.

The a7RIII and 5D MkIV both shoot high-quality 4K video.

Image quality

With both cameras boasting high resolutions, photographers will be able to make huge prints using images from these cameras – in fact, you’ll be able to get great looking prints well in excess of A3 size. The Canon’s largest file size measures 6720 x 4480, while the a7RIII’s largest file measures 7952 x 5304 and this means that photographers can crop heavily in on a frame to rejig a composition without compromising image quality. With the processors from both cameras helping to keep noise down, you can be assured that the 5D MkIV and a7RIII will supply images rich in colour and high in quality.

Other features & verdict

Both the a7RIII and the 5D MkIV share some great features, such as touch-sensitive LCDs, Wi-Fi to help transfer images to a phone or computer and a hotshoe flash mount for photographers to add a flashgun or a trigger to fire off-camera flash. But there are a few differences in the additional features too, with the a7RIII benefitting from Bluetooth and the 5D MkIV featuring timelapse.

Overall, these are two cameras that are packed with cutting edge technology and amazing features that will help photographers produce top quality imagery and video content. The a7RIII has enabled Sony to catch, and in some departments, overtake Canon with the a7RIII coming out top in terms of resolution, autofocus and burst mode. The Canon is still the camera to go for if you’re going to be on the road for long periods of time, working in harsh conditions. Both cameras are suitable for pro video use and have plenty of compatible lenses to choose from.

Sony a7RIIICanon 5D MkIV
Price$ 2,490.00$ 2,139.00
Sensor42.5-megapixel full-frame30-megapixel full-frame
Lens mountE-mountEF-mount
5-axis ISX
Max native ISO3200025600
Max burst rate10FPS7FPS
AF points42561
LCD3-inch tilting3.2-inch fixed
Touch-sensitive LCD
4K Video
4K Photo modeX
Dual card slots