Sony Alpha A7R IV Review

Currently the second most expensive Sony digital camera, after the action-oriented A9 II
Sony Alpha A9 II, the A7R IV is by all means a high-end mirrorless which delivers all the key features expected by professional photographers. This includes full manual-controls, choice of metering patters, custom and Kelvin white-balance plus extensive Auto Exposure Bracketing capabilities. It supports external lighting via a hot-shoe and sync-port. There is no built-in flash, something which is rarely used by professionals anyway.

The headline feature of the Sony Alpha A7R IV is its 61 megapixels Full-Frame CMOS sensor. With this resolution, huge image can be printed and remain looking very sharp up to 40 x 26", which is even larger than a standard poster. Sony claims that this new sensor can capture 15-stops of dynamic-range which is higher than any other Full-Frame camera currently achieves, only significantly larger Medium Format digital cameras can reach 16-stops. As usual, maximum dynamic-range occurs at the lowest standard ISO of the sensor since noise clips off shadow details at higher levels. For the A7R IV, the native sensitivity is ISO 100.

Extending its ability to capture incredibly fine details, the A7R IV offers Multi-Shot modes to increase color-accuracy or resolution. The former captures 4 independent RAW files shifted by one photosite in each direction to cancel out the Bayer Color Filter Array which produces full-color information at every pixel. The latter captures 16 independent RAW files shifted by a ½-pixel twice in each direction, resulting in both full-color details and 4X the resolution. The final output contains 240 megapixels! In either modes through, the set of RAW files captures must be processed on a computer to produce the final output. The photographer and the entire scene must remain completely still during the capture.

Sony mirrorless camera use the E-mount with many native lenses available from ultra-wide and to super-telephoto. Numerous third-parties make lenses for Sony E-mount which are compatible to full-frame. Sony also makes two A-to-E mount adapters for full-frame, one that supports autofocus and one without. This allows photographers to mount lenses for Minolta A-mount which was acquired by Sony years ago. The Alpha A7R IV sports a 5-axis built-in image-stabilization system that is effective to 5½-stops over hand holding. Since the mechanism is built right into the camera, it works with all lenses, even adapted ones. An in-camera setting allows users to manually enter the focal-length for lenses which do not report it to the camera.

This mirrorless has a fairly standard exposure latitude. The sensor supports ISO 100-32000 standard sensitivities which is expandable to ISO 50-102400. Combined with shutter-speeds from 1/8000 to 30s, this allows the A7R IV to capture fast-action and night photography. A Bulb mode of undisclosed limit allows the shutter to be kept open longer to photograph light and star trails. Ultra-fast action though cannot be frozen without using a flash to exceed the 1/8000s shutter-speed limit.

There are more Metering Modes on the Sony Alpha A7R IV than usual. The typical Multi-Segment, Center-Weighed and Spot are all there, plus Average and Highlight Weighed metering. Spot even comes in two sizes. Highlight Weighed meters the scene according to the brightest spot in the image. AEB and WB Bracketing are offered to try out the optimum exposure or WB Fine-Tuning, respectively. This is the minimum set of bracketing modes for a high-end camera with Flash and Focus Bracketing notably absent. Focus Bracketing, in particular, is impossible to perform manually in a reliable and repeatable way, so it is a shame that this camera is missing this feature. Another missing related feature is Built-in HDR. This one though can easy be done by computer.

The huge detailed files from the Sony A7R IV take a considerable amount of space and require plenty of processing power from the camera. The internal buffer can hold 68 files while they are being processed and it does not matter if those are Compressed RAW files or JPEG images. In fully uncompressed mode, the buffer holds just 30 frames. The continuous drive of this camera can reach 10 FPS, although AF and AE become less reliable past 8 FPS. Still, the Sony attempts to keep up. For such a high-resolution camera, this is quite fast yet it does not compare to the latest action-oriented mirrorless digital cameras. Drives modes are also minimal. There is a Self-Timer and a Continuous Self-Timer. Both allow 2, 5 or 10s intervals but the Continuous version captures a small burst after the interval has elapsed. In practice, this is almost useless since the shutter-shock makes all but the first frame blurry unless using a very fast shutter-speed.

Sony famously makes very reliable tacking autofocus systems and the A7R IV is no exception. Its 61 megapixels CMOS sensor packs a 567-Point Phase-Detection AF system that can follow objects across most of the sensor area. The system combines Phase-Detect and Contrast-Detect to track faces and eyes with high precision. There a plenty of focus area selection modes and settings to tune the speed and performance of autofocus. Manual Focus is obviously possible and both Electronic-Magnification and Focus Peaking assist in achieve precise focus.

Interval Shooting offers some flexibility for capture a series of images at a steady pace. Up to 9999 frames can be captured with intervals from one second to one minute. The starting of the sequence can be up to 99 minutes and 59 seconds ahead. This is a relatively limited set of options. Notably absent is the ability to produce a Time-Lapse Video in-camera. This is too bad since it greatly reduces the volume of data produced given that even 4K video is just made of roughly 8 MP images with inter-frame compression.

Both 4K Ultra-HD and 1080p Full-HD video can be recorded by the A7R IV. There are several frames rates available, up to 30 FPS for 4K and 120 FPS for 1080p. In addition to the usual Video Mode that writes videos with the same frame-rate as the recording-rate, there is a Slow&Quick mode that captures 1080p video at 1 to 120 FPS for playback at 24-60 FPS which results in video playing from 5X slower to 60X fast. Video capture allows the use of full manual-controls. Its 567-Point Phase-Detect AF system makes it possible to smoothly autofocus continuous while filming. Sony provides 3 levels of AF Speed and 2 levels of Tracking Sensitivity for videographers to compromize between accuracy and sudden changes.

Stereo audio may be recorded internally or externally. External audio can be captured by a standard mini-jack or via the new digital interface in the new Multi-Function Hot-Shoe. A special microphone is required. Currently this is only the Sony ECM-B1M which is available from B&H Photo and Adorama. Optional Wind Noise Reduction can be applied to the audio feed.

Professionals will appreciate the improved weatherproof body of this mirrorless and its dual SDXC UHS-II memory card slots. The slots can be used to extend storage, separate images by type or images from video or provide an instant backup. Unfortunately, the latter becomes difficult o manage since images can only be deleted from one card at a time. This will cause one card to fill up before the other and prevent further shooting until space is freed. Another issue with the cards is that the camera gets confused and shows an error when files are deleted outside of the camera.

Where the A7R IV truly abounds is in terms of connectivity. This camera supports WiFi 802.11ac, Bluetooth 4.1 and NFC wireless standards. Bluetooth is used to communicate with a smartphone for remote control or to get location data to save with each image. Standalone Bluetooth, Infrared and Wired remote controls are all supported. There is a built-in FTP server in the camera too! Both USB-C and Micro USB connectors allow the camera to be connected to a computer, power the camera and charge the battery internally.