Sony a7R IV review: Sony Alpha 7R IV with 61 Mpx- Mirrorless High-End Camera

With the Sony a7R IV (Alpha 7R IV ILCE-7RM4) Sony presents the currently highest resolution full format camera: 61 megapixels are accommodated by the Japanese electronics group on the back-exposed CMOS sensor.

But the Sony a7R IV can also boast other highlights, such as ten continuous frames per second, the 4K video function with 6K oversampling, the improved ergonomic and robust housing, the higher resolution viewfinder and the real-time autofocus familiar from the Alpha 9.

The “R” in the camera name makes a difference, as we explained here.

We have already reviewed the predecessor, the a7R III. In the past, we had also the opportunity to review the Sony a7R II. We have in this article, a comparison between the a7R III vs the a9.

Sony a7R IV Pros And Cons

Pros

• Excellently manufactured, weatherproof housing
• Very good ergonomics with high individualization
• High-resolution electronic viewfinder

• Insufficient integration of the touch screen
• High resolution can only be used under very special conditions
• Picture quality decreases noticeably with increasing sensitivity
• Strong Crop in 4K video recording
• Image storage might be faster, especially with JPEG

With 61 megapixels, the Sony Alpha 7R IV is the new resolution queen among full-frame cameras. On top of that, it also offers ten continuous frames per second and a fast real-time tracking autofocus. [Photo: Sony]

With 61 megapixels, the Sony Alpha 7R IV is currently the highest resolution full format system camera on the market (reviewed mid 2020). In addition, it is to focus quickly with 567 phase AF sensors integrated on the sensor, and despite the high resolution it is even to achieve ten continuous images per second.

Even the robustness and ergonomics of the housing are to achieve a new quality. What picture quality can be achieved with Sony at all, how it performs at higher ISO sensitivities and much more can be found in our detailed test.

The resolution of the full format sensor is also interesting under another aspect: in the APS-C-cropping mode, the resolution is of 26 megapixels, as it is currently available at Fujifilm in the APS-C format and if one crops the medium format camera Fujifilm GFX100 on the 35mm format, one also gets approximately 61 megapixels.

This means that all cameras have the same pixel density, which should, therefore, correspond to the current state of the art in larger image sensors suitable for practical use. Smaller sensors or prototypes from the development departments of manufacturers naturally achieve higher resolutions and/or pixel densities.

The Sony Alpha 7R IV has a very robust metal housing, which is well sealed against the penetration of dust and splash water with numerous seals. [Photo: Sony]

The sensor is back-illuminated so that the conductive tracks, which are applied during production after the light-sensitive layer, do not shadow the light-sensitive surface. This increases the light yield and was already state of the art with the previous model.

Moreover, Sony promises 15 f-stops dynamic range for photos (14 f-stops for videos), so that the image sensor should deliver “medium format quality” in total (the Fujifilm GFX100 has probably been excluded). The new, even more, powerful Bionz X image processor is also partly responsible for this.

567 phase AF sensors are mounted on the image sensor, covering 74 percent of the image area. In APS-C crop mode, there are 325 AF points, which cover almost 100 percent.

Sony is bringing the latest technology in autofocus to the Sony a7R IV: the real-time autofocus familiar from the Alpha 9 is now being used for the first time in the 7R series. It tracks the subject without interruption at up to ten continuous frames per second, of which the Alpha 7R IV 68 can take in one go, and the exposure is of course also adjusted. But real-time AF also extends to face detection, eye detection, and animal eye detection, which means that it is virtually unable to lose focus on the subject.

The Sony Alpha 7R IV has an improved focus joystick and an electronic viewfinder with 5.76 million pixels of significantly higher resolution. The Sony Alpha 7R IV’s touchscreen is very bright and at least movable up and down, but the touch control is only poorly integrated into the overall ergonomics. [Photo: Sony]

The Sony Alpha 7R IV’s 35mm sensor has a resolution of 61 megapixels. It thus offers the same pixel density as the Fujifilm GFX100 medium format camera or the Fujifilm X-T3 APS-C camera. [Photo: Sony]

For image stabilization, the full format sensor is mounted on a movable base, as in earlier Alpha models. It should be able to compensate for five axes of movement, including the axis of rotation. Up to 5.5 f-stops, longer exposure times are promised by Sony at your fingertips.

Sony also promises to have reduced vibrations caused by the mechanical shutter. If the 61 megapixels are not enough for you, you can take high-resolution photos from a tripod using the sensor-shift.

The Sony a7R IV takes 16 photos with a half or one pixel offset each, 963 megapixels should be created. From this, Sony’s desktop software “Imaging Edge” then calculates photos with a resolution of 240 megapixels or 19,008 x 12,672 pixels.

But the Sony a7R IV doesn’t only have many technical innovations, the case and ergonomics have also been revised. The handle is now better shaped, the metal shells have been redesigned to be more robust and the seals have been improved to protect against splash water and dust.

The exposure-compensation wheel now has a lock and the AF joystick has become larger. In addition, up to ten camera configurations can be saved on the memory card and loaded into other cameras of the same type.

In the course of the improved ergonomics, there is also a new VG-C4EM portrait format handle, which holds two batteries. Incidentally, thanks to its greater energy efficiency, the Sony Alpha 7R IV now achieves 670 shots according to the CIPA standard when using the rear screen or 530 shots when using the electronic viewfinder.

The Sony a7R IV should fit more securely and ergonomically in the hand thanks to the better-shaped grip. [Photo: Sony]

The Sony Alpha 7R IV exposure-compensation wheel can now be locked in the same way as the program dial. [Photo: Sony]

In addition, a 5.76 million pixel OLED viewfinder is now in use, bringing Sony up to par with Panasonic’s S-Series.

It magnifies 0.78x and offers a refresh rate of either 60 or 120 frames per second. The rear touch screen remains at 7.5 centimeters in size, resolves 1.44 million pixels and can be folded up and down. The memory card slot is the first to use a double UHS-II slot, so both SD card slots accept SDHC or SDXC memory cards with UHS-II standard.

This is the first time Sony has abandoned compatibility with the memory stick, as this was not possible at the same time as UHS-II.

Sony would also like to meet higher demands with the video function. Thus, the Sony a7R IV takes a maximum of 30 frames per second in 4K resolution (unfortunately not 60p, unlike Panasonic).

The camera operates in Super35mm mode (roughly equivalent to an APS-C crop) with 6K oversampling to achieve higher image quality.

For the first time, real-time eye-tracking autofocus is also available in the video function – not even the Alpha 9 can do that. Flat tone value curves (e.g. S-Log 3) offer video professionals extensive editing options, while Sony promises 14 f-stops of dynamic range. But also HLG for HDR videos that can be played directly on compatible TVs is supported.

For the first time in a Sony, the Sony a7R IV uses a dual UHS-II SD card slot. The compatibility to the MemoryStick is not applicable. [Photo: Sony]

The new Sony VG-C4EM portrait format handle, which is compatible with the Sony a7R IV, accommodates two batteries. [Photo: Sony]

A new feature is the digital audio interface via the multifunctional flash shoe. For the first time, microphones and other audio adapters can now send digital sound to the camera instead of analog.

Sony offers a matching microphone and an XLR adapter, but both can alternatively output analog audio signals due to backward compatibility.

The ECM-B1M digital microphone has eight microphones arranged in a row for adjustable characteristics. A DSP (digital signal processor) and an analog-to-digital converter are built directly into the microphone. It is available since December 2019. The digital XLR adapter XLR-K3M costs 650 dollars is available since January 2020. It also offers a DSP and an AD converter. In most of the online stores I saw, it started to appear in April 2020 online.

Sony also goes to modern ways with the interfaces. The USB-3 type C interface is not only suitable for fast data transfers (now also via FTP directly to a server), but also for charging the camera battery (and the batteries in the optional battery handle) and for supplying power to the camera.

The WLAN not only operates at 2.4 GHz but also at 5 GHz, which enables faster transmissions.

Remote control from a PC is now possible for the first time at Sony via WLAN. Bluetooth is of course also on board; it enables, for example, the transmission of GPS data from the smartphone to the camera.

Since the end of 2019, the Sony a7R IV is available at a price of almost 4,000 dollars. The VG-C4EM portrait handle cost 450 dollars, available since April 2020 online.

Ergonomics and Workmanship

Although the Sony Alpha 7R IV is unmistakably a mirrorless full format system camera of Sony’s 7 series in terms of design language, the housing has been revised and improved in important points.

Although there have been improvements in new generations before, such as a more stable bayonet, the leap has never been more fundamental than with the Sony a7R IV . It is the first truly rugged Alpha in the 7-series that actually deserves the attribute splash and dust protection.

No matter whether on the memory card or battery compartment, the knobs or rotating wheels: You can see and feel the seals everywhere.

The housing consists of robust light metal shells and partly of plastic. Ready to use, the camera weighs just over 660 grams, which is not exactly a small amount and, together with the still compact dimensions, underlines the solid feel of the camera.

Light metal is used at the front, back, top and bottom, while the handle is made of plastic. This is cleverly solved because due to the grained rubber coating for better slip resistance, you won’t come into contact with the actual case material at this point anyway. It also enabled Sony to accommodate the radio antennas for NFC, Bluetooth, and dual-band WLAN.

The handle is now even better shaped and has a distinct hollow for the middle finger. The power lever, shutter release, front dial and other controls such as the two function buttons can be reached with the index finger.

The most difficult thing to do is to press the C1 button because you have to bend your finger a lot to do so. With a sufficiently heavy lens, the camera can also be carried loosely on the fingertips of the grip hand, but with light lenses, the balance is no longer right and the camera slips out of your hand if you don’t grip it firmly.

Many controls are also within reach for the right thumb, including the two rear control dials, focus joystick, four-way weight, function menu, AEL, and separate AF-On button. The exposure correction wheel now finally has a disengageable lock and can thus be secured against accidental adjustment.

The rotation lock of the program selector wheel, on the other hand, is always active, so that the wheel can only be rotated if the central unlock button is held down at the same time. Only the Menu and C3 function keys are located on the left side of the housing out of reach of the right hand.

The electronic viewfinder now boasts the latest technology, with a 0.78x magnification factor and a resolution of 5.76 million pixels. The overview for spectacle wearers is moderately good, it works better when using the dioptre compensation. However, sensitive natures will notice that the OLED panel flickers slightly.

The resolution, however, is so fine that you can hardly make out any pixels. Also overall the representation is very good, rich in contrast and without delay.

Both the brightness and the color of the viewfinder can be adjusted, whereby the latter, like an automatic brightness control, precedes the screen, which has to be adjusted manually.

The screen is a tiltable touch screen. It can be tilted 107 degrees up and 41 degrees down. The resolution is also quite fine with 1.44 million pixels, but the size with 7.5 centimeters is not too luxurious by today’s standards. It is also a 4:3 display; the black bars required for the native 3:2 aspect ratio are only shown on the bottom and are used to display some recording parameters.

The foldable frame would certainly offer space for a screen diagonal of almost nine centimeters, perhaps this will also be possible at some point in the camera sector with the almost borderless screen technology that is now used in many smartphones.

As already mentioned, you, unfortunately, have to control the brightness of the screen manually. After all, it achieves an excellent luminance of 1,075 cd/m² in “sunny” mode, which is actually quite sufficient for sunny environments.

The touch functionality is unfortunately limited to setting the autofocus point, neither the menus nor the playback function understands touch inputs. After all, the touch screen can also be used as a touch panel if desired in order to be able to move the autofocus point when looking through the viewfinder as an alternative to the focus joystick via the touch screen.

A limitable screen area facilitates operation. Otherwise, the Alpha 7R IV is bursting with settings. The menu is extremely rich, but navigation is quite simple. The menu pages are logically sorted and provided with appropriate categories.

Nevertheless, it is not easy to find certain functions when you search for them specifically. However, preferred menu items can be arranged in a separate menu.

The customizability continues with the function keys. No less than 100 functions are available for each configurable key. Of course, this requires a certain amount of training and regular work with the camera in order to internalize the individually configured operation and not to forget it again.

Since configuration is a lot of work, the camera settings can now be saved to the memory card, up to a maximum of ten can be saved. They can even be transferred to other 7R IV camera models. In addition to the keys, the function menu can also be arranged individually.

The live image in the viewfinder and on the screen also provides all the necessary overlays required in practice, from recording parameters, various guideline patterns, and a 3D spirit level to an exposure preview, depth-of-field preview, and a live histogram. This should leave nothing to be desired.

The Sony Alpha 7R IV’s altogether six interfaces are all located on the left side of the case behind three rubber flaps that can be opened via a kind of hinge (the rubber is attached to an axle).

Behind the lower flap there are two USB interfaces, one is the classic Micro-USB and the other a modern USB Type C connection. Both can be used to charge the battery – even when the camera is switched on and with any USB charger – and also for data transfer.

In addition, a remote release cable can be connected via the micro-USB socket if the camera is not to be released via Bluetooth remote control or smartphone remote control. There is also computer control software for the camera.

A micro HDMI interface and two 3.5 mm jack sockets are located behind the upper, elongated flap. With the HDMI interface, we would have liked a larger and also more robust mini interface in view of the Alpha 7R IV’s video capabilities.

The upper 3.5mm socket is for the stereo microphone connection, and phantom power is not missing here either. A headphone can be connected via the lower socket for sound control.

Finally, under the front flap is a studio flash connection (F socket). But the hot shoe on the viewfinder can also be called an interface, because here not only system flash units can be connected electronically and mechanically to the camera, but even a digital microphone for video recordings can be connected.

This promises an even better sound quality when using appropriate microphones.

The exposure correction wheel of the Sony Alpha 7R IV now finally has an activatable lock. Thanks to its digital interface, the hot shoe even offers the possibility of connecting digital video microphones. [Photo: Sony]

On the right side of the case is the double memory card slot, which also has a new feature. For the first time at Sony, both compartments for SDHC and SDXC are compatible with the fast UHS-II, for which Sony has sacrificed compatibility with its own memory sticks.

Unfortunately, the UHS-II interfaces are not very fast. Even with an almost 300 MB/s fast Sony memory card, we only achieved a maximum write speed of 105 MB/s, which is only slightly above the UHS-I level.

It is also a pity that the memory cards are inserted the wrong way round, the labeling points away from the photographer, and is covered by the open flap.

The lithium-ion battery on the underside of the camera is also inserted upside down, with the flat side facing the outside of the camera and the curves towards the tripod socket. But this is ultimately a matter of getting used to, just like with memory cards.

Not only the long endurance per battery charge is to be emphasized positively, 670 pictures are possible according to CIPA standard measuring procedures when using the screen (with the viewfinder the endurance decreases to 530 pictures), but also the flexible charging possibilities via USB directly in the camera or even externally.

Moreover, instead of the battery, it is also possible to attach a portrait format handle that then takes up two batteries and therewith extends the endurance even more.

Sony also offers an external holder for four batteries to keep the camera mobile (for example when shooting video) for even longer. By the way, the tripod thread on the bottom of the camera is, of course, located in the optical axis, and also the distance to the battery compartment is very generous so that even some big quick-release plates do not obstruct the access.

Equipment And Features

It’s hard to believe, but despite its high price of almost 4,000 dollars (without lens, of course) and the enormous resolution of 61 megapixels, the Sony Alpha 7R IV actually has a fully automatic mode with scene recognition.

Thus, those who have a lot of money, need a high resolution but don’t want to bother with technical camera settings can definitely go for Sony.

Even a wide range of digital filters up to the toy camera is available. However, the Alpha 7R IV only develops its full power when the shooting parameters are specifically adapted to the subject situation, which can be done in Program, Shutter or Aperture Priority AE as well as in Manual mode, and if desired also with ISO Automatic.

 

The Sony Alpha 7R IV has a well-shaped, large handle that provides a secure grip and good ergonomics. [Photo: Sony]

 

These include extensive exposure bracketing functions that are not limited to exposure time only, but also white balance and DRO shooting series are possible.

DRO is Sony’s dynamic range optimizer that brightens shadows and protects the drawing in the highlights. Normal bracketing is possible with up to nine shots with up to one EV exposure difference between the images and with three or five shots up to three EV exposure differences.

This is completely sufficient for HDR recordings, which cannot be assembled in the camera, however. Also not to be added up in the camera are the Pixel Shift Multi-Shooting shots, where up to 16 shots can be added up on the computer to a dizzying 240-megapixel resolution.

The sensor-shift image stabilizer is used here, which should allow up to 5.5 EV longer exposure times from the freehand. If you use it for a maximum of four f-stops, you’re on the safe side, and above that the number of blurred shots increases noticeably.

For a full format camera with a large moving sensor mass, however, the system works extremely well. After all, one must not forget the enormous sensor resolution, which makes even the smallest shake visible with appropriate magnification.

The focusing is also not uncritical in view of the high sensor resolution. Here, a mirrorless system camera has an enormous advantage over a DSLR that the measurement is made directly on the image plane and not by deflecting the beam path via auxiliary mirrors.

When looking at the autofocus settings, it is noticeable that a balance of focus accuracy and shutter priority is preset not only for tracking AF but also for single AF mode. Fortunately, this can be corrected, as in order to make the most of the 61 megapixels, you want to have an autofocus that sits as securely as possible before taking the picture.

When measuring the autofocus speed in this mode, however, a small disadvantage of the enormous sensor resolution also becomes apparent: the Sony a7R IV does need a touch longer to achieve the necessary precision and, although it does not achieve record values, it is still fast at around a third of a second.

Another positive feature is the pure shutter release delay of only 0.03 seconds. Not only a DSLR with a folding mirror can hardly keep up, but even some other mirrorless system cameras cannot. Of course, it is an advantage that the Sony measures with working aperture so that the aperture does not have to be closed before releasing the shutter.

But the autofocus of the Sony Alpha 7R IV can be completely different if necessary. In pursuit mode, it is extremely fast and recognizes not only faces, but also the eyes of people or, optionally, animals. Even at ten continuous frames per second, the autofocus is adjusted without interruption.

Depending on the performance, various parameters are also available for configuration, for example, to combine some AF points into a group. In general, the autofocus with 425 contrast and 567 phase measuring points integrated on the sensor offers a rich AF measuring density over a large area of the image sensor.

The Sony Alpha 7R IV easily achieves the promised ten continuous frames per second and, despite the enormous resolution in raw, even holds out for 73 instead of the promised 68 frames; in JPEG X-Tra-Fine, on the other hand, it is “only” 67 frames.

Enormous amounts of data accumulate with 60 megabytes for a loss-free compressed 14-bit raw or 50 megabytes for a JPEG. It becomes interesting when the buffer is full and how long it takes to empty it again.

In Raw, with a fast memory card, this can be done permanently at 1.8 frames per second, whereas in JPEG it is only 0.5 frames per second. The significant difference is also evident when emptying the buffer, which takes only 21 seconds in Raw, but almost two minutes in JPEG (115 seconds is exact).

The eye of the needle is not the amount of data, but the image processing, which despite the powerful Bionz-X image processor with front-end LSI auxiliary processor takes up an enormous amount of time – not least because lens errors are also digitally compensated.

Since some camera settings are locked when writing the images, it can be a bit annoying in JPEG to wait for the buffer to empty. Thus, those who do not need the images immediately but can also develop them later on the computer should actually use the raw instead of the JPEG format for faster reaction times in action shots.

Up to now, this has actually been the other way round. The only about 20 percent larger data volume of the raw recordings is rather less significant with the Sony Alpha 7R IV.

The opposite of continuous shooting action shots is the interval function, which has finally found its way into the Alpha-7 series. With adjustable start time and interval, up to 9999 shots are possible. Practically, the total recording time is already calculated in advance, so that one can also estimate without a pocket calculator if the desired recording time is reached.

With a three-second interval, for example, you can run interval recording for up to eight hours and 20 minutes, for example, to record the starry sky. At 24 frames per second, this would result in a seven-minute film, which could easily be rendered in 8K or higher due to the high resolution.

Further settings allow a slow adjustment of the exposure time and a selectable prioritization of exposure time or interval time if they overlap. Silent recording with an electronic shutter is also possible.

 

With a flash sync socket, microphone input and headphone output, micro HDMI and two USB interfaces (micro and type C), the Sony a7R IV offers numerous interfaces. Bluetooth, dual-band WLAN and NFC are also added. [Photo: Sony]

Speaking of the shutter: This offers a setting range from 30 seconds to 1/8,000 second, whether electronic or mechanical. The closure sounds pleasantly rich, but not too loud. However, the bulb function is only available with a mechanical shutter. In addition, the mechanical work of the closure is quite noticeable. Certainly not without reason, an electronic first shutter curtain can be activated to reduce vibrations.

The video function of the Sony Alpha 7R IV is also impressive. One might think that it is not so well suited for video recording due to the high pixel density, but this is not the case. The 4K video function operates with 6K oversampling, which provides higher image quality.

However, the high resolution only allows a maximum of 30 frames per second. Thereby, the enormous image cropping to the Super 35mm format that is approximately the size of APS-C is immediately noticeable.

If, on the other hand, you switch to Full-HD, the full image width of the 35 mm sensor is used. Somewhat annoying is also the restriction of the refresh rates, which is bound to the PAL and NTSC format.

In PAL, only 25 frames per second (in Full-HD also 50 or 100p) can be recorded, whereas in NTSC 24, 30, 60 and 120 frames per second are possible depending on the resolution. In view of the otherwise free programmability of the function, this seems downright grotesque.

The mechanical sensor-shift and optical image stabilizer of the lens are active during video recording; there is no electronic image stabilizer that would further limit the recording area used.

A level meter is available for sound recording, instead of the internal stereo microphone, analog and digital can be connected externally, and sound control via headphones is also available. The signal can also be recorded externally via the HDMI interface. Internally, “only” 100 Mbit/s are available as the maximum quality.

In contrast to photo recording, HDR recording according to the HLG standard is also available here, and other tonal value settings common in professional video recording are also possible.

A proxy recording function in HD resolution is also available. Almost the entire power of the autofocus functions can also be used and configured, including real-time human face and eye autofocus.

The wireless connectivity of the Sony Alpha 7R IV gives everything that is technically possible and useful today. In addition to Bluetooth-LE, these include NFC as well as dual-band WLAN with 2.4 and 5 GHz and all current WLAN transmission speeds such as N or AC.

This allows the Sony a7R IV to be triggered remotely via Bluetooth or WLAN, including live image transmission to a smartphone and configuration of the recording parameters. Sony also offers a Bluetooth remote control.

The geotagging function is also implemented via Bluetooth, using the GPS (or all available positioning systems) of the connected smartphone. The 7R IV also supports background FTP data transfer via WLAN and, of course, remote control from the computer, also wirelessly via WLAN or even via USB cable.

The tripod thread of the Sony Alpha 7R IV sits in the optical axis, the distance to the battery compartment is generous. [Photo: Sony]

Connection With TV And Wireless Speakers

The playback function, on the other hand, is less lavish. Image or video editing is not possible here, but at least a slide show can be played back, via HDMI also on a TV including control via the TV remote control. Therefore, I made a connection with an old Pioneer Kuro for the images and for the sound, the wireless speakers Devialet. I could watch the recorded video on the Kuro TV and hear it in the Devialet Phantom Gold. A complete luxury.

The Sony a7R IV also offers direct printing functions. The image rating function is also useful so that you can mark your favorites on the camera.

Image Quality Of The Sony a7R IV

With 61 megapixels on a 35 mm sensor, the Sony Alpha 7R IV currently offers the highest resolution in 35 mm format.

The pixel density corresponds to a 26-megapixel APS-C sensor or the 100-megapixel medium format sensor of the Fujifilm GFX 100, while Canon, with the M6 Mark II and the 90D in APS-C format, as well as Olympus and Panasonic with 20 megapixels in Micro Four Thirds, are already achieving higher pixel densities, so that higher resolutions are conceivable in the future.

But does that make sense at all? On the one hand, lens defects become more and more visible with increasing pixel density, or the demands on the lenses increase.

The larger the image circle of the lens, the more difficult and expensive it is to minimize lens flaws.

On the other hand, the Sony Alpha 7R III with 42 megapixels offers an excellent balance of high resolution and good high-ISO performance. This goes so far that the 7R III, scaled down to twelve megapixels at maximum sensitivity, still captures more details with less noise on the sensor than the native twelve-megapixel resolution Alpha 7S II, which also achieves even higher sensitivities, but no longer delivers usable image quality.

Sony sells the Alpha 7R IV without a set of lens, so we decided to go with the FE 24-105 mm F4 G OSS, which has so far scored very well in terms of performance and resolution. We also had the opportunity to test the new FE 35 mm F1.8 on the Alpha 7R IV.

Surely neither of these are super high priced high-end lenses, you have to keep that in mind. On the other hand, the Alpha 7R IV will mercilessly show the limits especially of the 24-105 mm, as will be shown below.

We’ll be conducting Sony lens tests with the 7R IV in the future, and there will certainly be a lens that the camera will not push to the limit.

In order to make use of the 61 megapixels of the full format sensor of the Sony Alpha 7R IV, not only a high-end lens is required, but also images with aperture F4 and ISO 100 [Photo: Sony]

The Sony Alpha 7R IV achieves the highest resolution at 50 percent contrast with the 35mm lens. With 101.6 line pairs per millimeter (lp/mm) at F4, the Alpha 7R III is easily outdone.

However, the 50 megapixel Canon EOS 5DS R remains the leader in our full-frame lab tests with 102.4 lp/mm, achieved with the EF 35 mm 1.4 L II USM at also F4.

A phenomenon that had already been seen with the Canon is repeated with the Sony: already at F5.6 the resolution decreases again due to diffraction, but at less than F4, 100 lp/mm is also not reached.

This is not different from the FE 24-105 mm, only that it starts already at F4 and already loses resolution when fading, except in telescopic position. In the telephoto position the sweet spot is F5.6, but here the music is below 80 lp/mm. Overall, this means that the resolution of the Sony Alpha 7R IV can only be fully exploited at a fairly shallow depth of field. If you like to zoom down to F8 or F11 for landscape shots, you will already lose ten to 20 percent of resolution.

At over 80 lp/mm at F11, this is whining on a high level, but this is where the physical-optical limits of pixel density become apparent.

As already anticipated at the beginning, the high-resolution sensor takes the FE 24-105 mm to its limits. The maximum resolution is just over 97 lp/mm at 24 mm and F4 in the center of the image. No matter if you fade, zoom or move towards the edge of the image, the resolution drops.

Up to F8, it is still 90 lp/mm in the middle of the picture, above that diffraction is stronger. The edge drop in resolution is enormous at 24 mm and open aperture, not even half of the resolution in the image center is achieved.

After all, the edge resolution increases with fading from 46 lp/mm at F4 to a maximum of 67 lp/mm at F8 and F11, so that the edge drop at F11 is less than 20 percent, which is good. With a medium focal length, the resolution of a maximum 75 lp/mm in the image center is clearly lower and it only knows one direction when fading down: downwards.

After all, it remains very constant from F5.6 to F11 at around 68 to 70 lp/mm. At the edge of the image, however, things look different, the edge fall-off at open aperture is high (about 40 percent) and the edge resolution low (45 lp/mm), but it even increases up to F16 to 64 lp/mm, and from F8 the edge fall-off is less than 20 percent. In telescopic position, the resolution in the center of the image is slightly better again and reaches more than 70 lp/mm from F4 to F8, at F5.6 it is even 78 lp/mm.

On the other hand, the marginal resolution is even lower, increasing from 45 lp/mm at open aperture to only 59 lp/mm at F16. A resolution drop of less than 20 percent towards the edge of the image does not occur in the telescopic position until F11.

After all, the color fringes, distortion and edge darkening are low, and here Sony’s digital correction, which leads to the long JPEG image processing times mentioned above, works very well.

But you don’t just need a very good lens for the Sony Alpha 7R IV, you also need a lot of light.

Above ISO 800, many measurement parameters tilt from the good to satisfactory range into the sufficient or even into the deficient range. The signal-to-noise ratio, for example, is only good at over 40 dB at ISO 50 and ISO 100, while at ISO 800 it is just about acceptable 35 dB.

The measured value of the brightness noise increases above ISO 400, above ISO 1.600 it becomes visible at the latest, above ISO 12.800 it becomes very strong and disturbing visible.

Only the color noise is better controlled by Sony, it only rises above ISO 12.800 and is only slightly visible at the two highest sensitivities of ISO 51.200 and 102.400. After all, the noise is always very fine-grained and does not form clusters with neighboring pixels.

Only at ISO 50 does the input dynamic reach over twelve f-stops and above ISO 800 it drops below eleven f-stops.

Nevertheless, the dynamic range up to ISO 6.400 with around ten aperture stops still remains within the green zone. The tone curve is steeply sloped for crisper center contrasts and more vivid images. The output tonal range is very good at ISO 50 and 100 with over 224 of 256 possible brightness levels, but it decreases steadily and already leaves the good range at ISO 800 with less than 160 levels and even scratches the bad range at ISO 6.400 with 100 levels, in which all higher ISO sensitivities are located.

The color deviation is good on average, but the strongest deviations are definitely medium strong, whereby especially the range from orange to red to magenta stands out due to its increased saturation.

Sony also relies on subjectively beautiful looking pictures instead of neutral ones. But this is not meant negatively from this point on, as in our opinion, a JPEG should look crisp and beautiful without image editing, for everything else the raw data format is better anyway.

Both memory card slots of the Sony Alpha 7R IV are USH-II compatible but don’t use nearly the speed potential. The battery, on the other hand, gets a lot of praise for its endurance and the flexible charging options. [Photo: Sony]

So far we have ignored texture sharpness, the value that indicates how much detail is lost at higher sensitivities due to noise or – even worse – due to noise reduction.

In this respect, the Sony does quite well in view of the other readings that we determine via the ISO sensitivity spectrum. Up to ISO 3,200, fine details become well-differentiated, even if not 100%.

From ISO 6.400 on, however, the level of detail also decreases. In principle, the curve is identical to that of the Alpha 7R III, but with one important difference: the level of the IIIs is significantly higher throughout. The difference is a good two ISO levels. This clearly shows that Sony has reached the limits of what is possible with current technology with 61 megapixels.

From a purely visual point of view, the Alpha 7R IV’s images are still quite useful at ISO 6.400, but at ISO 12.800 they are already noticeably worse. With the 7R III, however, this leap only occurs from ISO 12,800 to 51,200 with a fine intermediate step at ISO 25,600.

Conclusion: Is The Sony a7R IV Worth It?

The Sony Alpha 7R IV is an excellent camera in many respects and a clear step forward compared to the 7R III, and of course, with the a7R II.

For example in terms of the robustness of the housing including the ergonomics and the user interface, not least because of the good viewfinder.

The performance and video capabilities are also impressive, even if there are first limitations, such as slow JPEG data processing or strong crop in 4K videos.

In addition, the UHS-II data interface falls far short of the possibilities. However, the step to 61-megapixel resolution is afflicted with the biggest compromises.

So you not only need a correspondingly good high-end lens to be able to exploit the resolution at all, but you also have to fade in quite far (F4) in order not to lose any resolution through diffraction blur. On top of that, the high image quality is practically only available at ISO 100, as soon as the sensitivity increases, one quality criterion after the other tilts from the good to very good range into the satisfying or further below.

Laboratory values above ISO 800 already show significant losses, but ISO 6,400 is still usable if you turn a visual eye. Thus the advantage of the resolution is limited to a narrow band of recording parameters, which also costs a lot for the camera and the necessary high-end lens.

From this point of view, the Sony Alpha 7R III is the biggest competitor to the Sony a7R IV in terms of image quality and the more universal camera.

The Digital Microphone for the Sony Alpha 7R IV

The new digital microphone for the Sony Alpha 7R IV from Sony’s live presentation [Photo: Sony]

The new digital microphone for the Sony Alpha 7R IV from Sony’s live presentation [Photo: Sony]

Controls of the new digital microphone for the Sony Alpha 7R IV from Sony’s live presentation [Photo: Sony]

Sony a7R IV Datasheet