The highlight of the A7R IV is of course that 61-megapixel BSI CMOS sensor, which Sony claims is the first of its kind. Sony's Pixel Shift Multi Shooting is also present, which shoots 16 high-resolution images, with a slight shift in sensor positioning for each image, either by one or half a pixel. You can then composite all the images in Sony's Imaging Edge software, for an effective 240.8-megapixel resolution image.
Some of the basic specifications include an ISO range of 100-32,000 (expandable), 567 PDAF and 425 contrast detection autofocus points, E-mount, and Sony's BIONZ X image processor. The new camera might look similar to the older model but Sony says it has made some upgrades to the design and usability. The aluminium alloy body gets additional sealing at all the seams for dust and moisture resistance. There's a wider hand grip, new multi-selector joystick, and redesigned shape and position of the rear dial. Both card slots are also UHS-II compliant.
The A7R IV also debuts real-time Eye AF when shooting movies and also supports Eye AF for humans and animals. It also has a OLED EVF with a 5.76 million dot resolution, which is the highest yet for a Sony full-frame camera. There's also professional 4K video recording modes that shoot at the full resolution with no pixel binning in Super 35 mode. S-Log3 and HDR workflows are also supported. Burst shooting is an impressive 10fps with AE/AF tracking for about seven seconds and is three times longer, when shooting in cropped (APS-C) mode. The battery is rated to deliver approximately 670 shots per charge, when using the LCD.
Sony also announced a bunch of new accessories for the A7R IV. These include VG-C4EM vertical grip, which also has in-built batteries for prolonged battery life. This also goes on sale in September for $400. Sony also announced the ECM-B1M shotgun microphone, XLR-K3M XLR adopter kit, which go on sale in September and October for $350 and $600 respectively.