SONY α7RIIIA.

ON ITS OWN WAY.

October 17, 2025.
The Sony α7RIIIA (ILCE-7RM3A) is a photographic camera with an electronic viewfinder and a 36 mm image sensor. The device was first introduced on October 25, 2017. On April 7, 2021, a new, A marked version was released, which is a slight improvement over the original model. As is customary with Sony, this A version is still on sale and at a very good price, approximately half the original price of the α7RIII. So let's take a closer look at the Sony α7RIIIA.


IMAGE SENSOR.
The heart of the Sony α7RIIIA is the Sony Exmor-R image sensor, consisting of 43.6 million light-sensitive elements, of which 42.2 million create the actual photograph. The aspect ratio of the sensor is 3 : 2, so the photographs consist of 7952 x 5304, i.e. 42 177 408 pixels. As the letter R (Resolution) in the name suggests, the sensor is not equipped with an AA (OLP) filter, that reduces image quality and is unnecessary for photography. The sensor is a BSI CMOS type, with BSI being an abbreviation for Back Side Illuminated. Which, as I have already written in several articles, does not really mean, that there is a some small lamp inside the camera on the back of the sensor, as we sometimes read somewhere. It is just a designation of the reverse construction, than was common in older sensors. In very simple terms, most of the components, that were previously located between the individual optical elements, have been moved to the back of the sensor. This eliminates light reflections from these components, which sometimes reduced the level of the captured image. It is also possible to cool these components better, which leads to higher quality and reduced noise. In conjunction with the BIONZ X processor, a dynamic range of up to 15 EV can be supposedly achieved at low sensitivities. The sensitivity range is standard ISO 100 - 32 000, and can be expanded to ISO 50 - 102 400. Image processing is 16-bit, with the resulting image in RAW format usually being 14-bit. MECHANICAL IMAGE SENSOR STABILIZATION.
The image sensor is housed in a mechanical stabilization unit, that is capable of compensating for camera movements in five axes, thus achieving an increase in "holdable" exposure times by up to 5.5 EV.


QUALITY OF PHOTOGRAPHS.
The dynamic range is really surprisingly large, the colors beautifully clean and deep. Noise is minimal and if there is more of it, e.g. at night at high sensitivities, it is very sharp and specific, which surprisingly contributes to the quality of the image and becomes an image-forming element. It is similar to films, when for example for some subjects materials with T- or Δ- crystals are used for their unique shape and grain structure, which are in themselves a significant creative element, co-creating the character of the photograph. So if I can compare various 36 mm Sony sensors, which I have been working with in many devices for a really long time, I can say, that they are all excellent, but Sony keeps the absolute best for itself. Whether it is the design, image processing or something extra, that it does not provide to its customers, no one except the manufacturer probably knows. The difference is noticeable, however, and the photographs have a different, unique character, which is very close to my personal taste, compared to, for example, the Nikon Z8. CAMERA BODY.
The Sony α7RIIIA camera body is made of magnesium alloy. It is completely sealed against dust and moisture. Of course, it is not waterproof, but there is no need to worry about short-term photographing in ordinary rain or dust. The body is relatively small, 12.7 cm wide, 7.4 cm deep (with a standard eyecup) and 9.7 cm high. Thanks to the precisely designed holder for the right hand, it holds very well, and the material used on the surface is also very pleasant and non-slip. The shutter release button is truly top-notch, which is metal and, unlike many other devices, quite protruding above the ring, in which it is mounted. Thanks to this, it is pleasantly sensitive and its move is relatively short. The front and rear wheels have a very precise, solid operation. The circular controls for exposure modes and exposure adjustments are metal, almost watch-like precision. The same can be said about the rear, third wheel, which is also a four-way selector with a button in the middle. In general, the entire Sony α7RIIIA camera gives the impression of a very expensive and precise wristwatch, so excellent is the overall workmanship and mastery of the necessary technological clearances. This is undoubtedly a positive effect of the longer production cycle of this device, when all problems and inaccuracies were gradually eliminated over the years. The matte dark gray body color and relatively sharp edges also contribute to the great impression. Compared to, for example, aforementioned Nikon Z8, whose body is largely made of plastic, the Sony α7RIIIA camera feels like a device at least twice expensive, if not more. In reality, however, the opposite is true.


MODEL A SPECIFICATIONS.
As mentioned in the introduction, the camera with the designation α7RIIIA (ILCE-7RM3A) was introduced on April 7, 2021. Compared to the original model, the resolution of the rear monitor was increased to 2.36 million dots and the USB interface speed was increased to 5 Gbps. BEWARE OF FIRMWARE.
The camera's firmware is updated and improved by the manufacturer from time to time. Therefore, after purchasing a new device, one of the first things to do is visit the manufacturer's website and see, what the latest firmware version is for our device. If the firmware in the camera is older, you need to update it. It is not difficult at all, it is usually described in great detail on the manufacturer's website, and I have never had a device that did not work properly. But ...

Some stores are treacherously selling the α7RIIIA camera as the α7RIII. There is apparently no bad intention in this, they are actually harming themselves by doing so, as they seem to be offering an older model. If you are not very familiar with Sony cameras, the missing letter A will not seem at all noticeable. You buy the device and look at, what version of the firmware is loaded on it. And surprisingly, you find out that it is 1.0. Which is the oldest, the first version, which is usually updated soon. In this case, it would be the version from autumn 2017, i.e. 8 years old. Well, hello. So you look at the manufacturer's website and find out, that the current firmware version for the α7RIII is 3.10. Hm, that's strange, you think. Either it is a very old product, that has been lying around in a warehouse for a long time, or the manufacturer still loads only the original, first firmware into the device and leaves all updates to the customer. In any case, you need to upload the new firmware immediately. So you download the appropriate 3.10 file, start the update and find out, that the update program (with Sony, the update is done by connecting the camera to the computer and running the update file) still claims, that it cannot see the connected camera. After some time, you try all your USB cables, restart the computer and the camera and if that still doesn't help, you start thinking about filing a complaint. Even on the box, most of the captions state, that there is an α7RIII camera inside. But only in the detailed description later do you find out, that this is not true and that it is an α7RIIIA, i.e. ILCE-7RM3A. So you look for the appropriate firmware for this type and see – the latest version is 1.0, in other words, no update has been released. It can be assumed, that version 1.0 for α7RIIIA is version 3.10 for α7RIII, but it contains slight modifications due to the new features of version A. In other words, an update is not necessary.





BEWARE OF MISSING LARGE PHOTOGRAPHS.
Most materials will tell you, that the Sony α7RIIIA camera has the Pixel Shift Multi Shooting function. This is the marketing name for the function, which uses sensor shifts to create 4 or 16 (sometimes even 32) photographs, which are then combined in a certain program on a computer. The result of combining 4 photographs is the removal of the unfortunate effect of the Bayer mosaic (I write a little more about this in the article about the ►Fujifilm GFX 100S II camera). By combining 16 or 32 photographs, we get a photograph with 4x higher resolution, than the basic resolution of the sensor. With the α7RIIIA, we should therefore be able to create almost 170 Mpx images (168.8 Mpx to be exact). Good, you think. But the bridge is wrong. Only after a detailed examination of the Pixel Shift Multi Shooting function manual for this model will you find out, that the α7RIIIA can only and only 4 images, i.e. only remove the Bayer's revenge. Image stitching for the purpose of creating high-resolution photographs is not available here. For this option, you need to buy a camera such as the α7RIVA or α7RV, if the AA filter is not a problem, then the α1 or α1II too.


FOR LONG EXPOSURE TIMES, NOT TOO.
If you mainly create night photographs or for any other reason use exposure times longer than 30 seconds, the Sony α7RIIIA is not very suitable for you:

• There is neither a T (Time) mode nor a timer in Bulb mode.
• The longest adjustable exposure time is 30 seconds only.
• In Silent Shutter mode, Bulb mode cannot be set at all. You have to use a mechanical shutter, which is inconvenient due to vibrations. Fortunately, you can at least turn on the so-called electronic front curtain, so the only problem remains the unnecessary use of a mechanical shutter, which always has a limited lifespan.
• In Bulb mode, the camera does not save photographs in 14-, but only in 12-bit color depth.
• When exposing in Bulb mode, no elapsed time information is displayed on the rear monitor.

It's briefly just an older concept, where we used to count down the times in Bulb mode out loud or measure them on a watch. It's not too big problem. Maybe controlling it from a connected phone would help, the timer could be there, I don't know, I haven't tried it. It's just a shame about the 12-bits, it's really unnecessary.


VIEWFINDER.
This part of the device is very important not only for photographic cameras with electronic viewfinders. The electronic viewfinder in the Sony α7RIIIA camera is called TruFinder. The monitor is the OLED type and consists of approximately 3.69 million dots. For a completely smooth display of fast-moving objects, the refresh rate can be increased from the default 100 to 120 frames per second. Of course, the well-known Carl Zeiss T* anti-reflective coatings are included, which suppress distracting reflections and prevent unwanted reduction in contrast.





ON ITS OWN WAY. AND VERY WELL.
Among cameras with an electronic viewfinder and a 36 mm sensor, Sony devices are among the smallest. Although the dimensions of newer devices are gradually being carefully increased, they are still, in the best sense of the word, tiny cameras. However, they hold up relatively well, which is a nice paradox. Sony also did not enlarge the mount and stayed with the original one, which brought many complications in the design of lenses, but did not prevent them from creating truly quality ones. For example, the FE 14 mm 1 : 1.8 GM, FE 12 - 24 mm 1 : 2.8 GM or 12 - 24 mm 1 : 4 G. The narrow mount diameter was a hard problem for very wide-angle lenses. How well the manufacturer coped with it testifies to the immense diligence and care, that ultimately led to the creation of truly great optics. And what is no less interesting, even cheap lenses with a fixed focal length can, if certain limitations are respected, be used to create top-notch large-format photographs. These include, for example, the FE 28 mm 1 : 2.0, the FE 50 mm 1 : 1.8 or the FE 85 mm 1 : 1.8.


THERE IS A ERROR.
Understandably and unsurprisingly, it's a combination of a photographic and a video camera. If you're a photographer, it's just annoying and you're paying for it unnecessarily. Especially with the R series, there should definitely be purely photographic models on offer.


CONCLUSION.
The Sony α7RIIIA is an older camera, but apart from minor shortcomings in creating photographs with long exposure times, this is almost not noticeable. Among cameras with 36 mm sensors, the photographs it creates are among the best. In terms of dynamics, color reproduction and overall noble, very artistic character. The body construction is at the level of the most expensive, hand-made devices, all now for half the original price. In addition, some stores offer a free three-year warranty extension for this camera directly from the manufacturer.


© Martin Mojzis, 2025.
Images: © Sony.

►To the beginning of the article.
►Overview of all articles.
►Homepage.
►Site Map.