The first in the line of Sony’s fourth-generation A7 cameras, the A7R IV is the high-megapixel, professional-grade mirrorless camera that has been highly anticipated ever since the launch of the A7R III almost two years ago.
Each generation of Sony’s A7 series mirrorless cameras consists of the A7R, favoured for high-resolution professional work, the A7S which boasts superb low-light capabilities and is ideal for video, and a regular A7 model. The line is years ahead of the mirrorless full-frame field with entrants from Nikon, Canon and Panasonic arriving in the past months.
The high-resolution A7R IV boasts the world’s first 35mm full-frame 61.0-megapixel (9504 x 6336p) back-illuminated Exmor R CMOS sensor, which is paired with the latest-generation BIONZ X image processing unit to crunch all the pixels. That’s well on the borders of medium format territory, with contenders such as the GFX 100 costing about USD 10,000 for the body alone.
With such a mind-numbing amount of pixels, Sony has redesigned the in-body image stabilisation system to reduce camera shake for absolute sharpness.
This far surpasses the Nikon Z7 at 45.7 megapixels and the Canon EOS R at 30.3 megapixels. The previous-generation A7R III had a resolution of 42.4 megapixels.
Despite the high megapixel count, the A7R II will boast a 15-stop dynamic range. This is a notch higher than the Nikon Z7, tested by DxOMark at 14.6 stops, and the Canon EOS R, at 13.5 stops. It’s a mild improvement over 2017’s A7R III at 14.7 stops.
The high megapixel count also means that continuous shooting can be sustained at 10 fps with full AF and AE tracking for approximately 7 seconds. This increases to 21 seconds when shooting in APS-C crop mode which reduces the resolution to a still-respectable 26.2-megapixels.
That’s exactly the same as the previous generation A7R III, which also boasts a 10 fps continuous shooting speed with full AF and AE tracking too.
Conversely, the Canon EOS R tops out at 5 fps with continuous AF, while the Nikon Z7 shoots up to 9 fps but with AE locked.
With 567 focal-plane phase-detection AF points covering 74% of the sensor, along with 425 contrast AF points, the A7R IV is ahead of its predecessor. The A7R III only had 399 phase-detect points covering 68% of the sensor, with a similar 425 contrast-detect AF points.
The Nikon sports 493 hybrid phase-detection autofocus points, but they cover 90% of the image area. The Canon EOS R boasts 5,655 selectable AF points with its class-leading Dual Pixel AF, with 100% horizontal and 90% vertical coverage of the image area.
The A7R IV debuts Real-time Eye AF for use in movie recording and stills
Viewfinder and LCD
At 5.76 million dots, the UXGA OLED Tru-Finder EVF on the A7R IV blows the Canon and Nikon (both 3.69M) out of the water, promising more true-to-life visual feedback.
Though not much is known about the LCD screen on the Sony A7R IV, it would likely lack the full articulation as found on the Canon EOS R series of mirrorless cameras.
The A7R IV will offer 5-axis in-body image stabilisation, which would likely be equal to or better than the 5.5 stops of compensation offered on its predecessor.
The Nikon Z7 offers 5 stops, while the Canon EOS R lacks any in-body stabilisation.
The Sony A7R IV is shaping up to be a true beast at video recording. With 4K 30P HDR recording without any pixel binning, the camera records 6K footage and downsamples it. It will support S-Log 2 and 3 for post-production.
That’s in contrast with the Canon EOS R, which induces a 1.6x crop factor when recording 4K video at similar frame rates, effectively changing the focal length of the lens used.
The Nikon offers image stabilisation in-body, along with 4K video recording without any crop, but lacks the eye autofocus for movies along with HDR support.
The A7R IV will also introduce a new proprietary digital audio interface, called the Multi Interface Shoe, built into the camera’s hot shoe slot that will enable direct recording via an add-on shotgun mic without adding any cable clutter or hassle. It will also support a new XLR microphone adapter.
Dust and weather resistance will also be enhanced on all gaskets, especially on the bottom of the A7R IV, along with broader ergonomics enhancements such as a new location for the thumb-operated dial.
Shutter lifespan has been increased to 500k, a new Pixel Shift option enables 240-megapixel images produced by 1/2 pixel shifts and 16 images, and the AF system does not need to stop the lens down in order to focus.
And yes, unlike all the Canon EOS R, RP and Nikon Z7, Z6 contenders, the Sony A7R IV offers dual UHS-II SD card slots. That’s one more UHS-II slot than before, meaning that transfer speeds and waiting times will be reduced – especially important given the huge image file sizes on the camera!