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Sony a7S iii specs and comparison

We ran out of nails to bite waiting for the release of the Sony a7S III but the wait is finally over. To celebrate we’ve gathered all of the technical specs here for our readers and also made a comparison table between the a7S III, a7s II,a7 III and a7R IV cameras which really shows how much technology Sony has squeezed into this professional mirrorless hybrid body. There are a couple of sample images as well as our video ‘first look’ at the Sony a7S III. Prepare to fall in love with creativity all over again!

*UPDATE* February 2021 Firmware and Alpha 1

Firmware Update for Sony a7S III camera

Sony has released free firmware update ILCE-7SM3 (Ver2.00)

  1. This adds the rich S-Cinetone picture profile preset, which can be used for monitoring or embedded directly into video footage to reduce colour grading requirements.
  2. Active Steady Shot with S&Q Frame Rate. Slow and Quick means you can shoot between 1fps to 120 fps, enabling time-lapse and slow motion effects.
  3. Overall camera stability improvements

Since the announcement of Sony’s A 1 camera, which is a new flagship model on its way later in spring 2021, we thought it was well worth updating this post with just how well the A7S III body compares.

  1. Availability - the A7S III is available now and in-stock. In other words, months ahead of the new A1 model. Supply chains have been disrupted throughout the world recently, which has delayed stock. If you want the latest Alpha body, there is only one choice at this moment, and it’s a good one.
  2. AF points. Both models boast 759 AF points which is the widest sensor coverage Sony has ever offered at over 90%. Wherever your subject is in the frame, the camera will be able to achieve focus quickly and efficiently.
  3. Price. Any flagship model comes at a price, in this case over £2500 more expensive than this incredibly competent video camera.
  4. Intended use - for some video capabilities combined with low-light mastery are all that they need. Having 12 megapixels is ample for on-screen work, digital files and even print 8x12 inch prints beautifully. Many simply don’t need 50MP images for their intended use. Videographers will reap the rewards of the A7S III.
  5. Video capabilities - With no overheating and 10-bit 4:2:2 internal recording with 4K video at 120p and 240p HD the only difference is future-proof 8K movies. Clearly 8K comes is highly desirable, but how long until we experience 8K for real? Cropping-in is invaluable with panning effects available in post production, but memory and processing demands will be high. For now we will be more than happy with the increase in colour afforded by 4:2:2 internal capture.
  6. Both cameras employ the same upgraded BIONZ XR image processor. It’s quite simply the fastest ever from Sony


We had bets in the virtual office to see what Sony might add to this new iteration of the a7S III. Perhaps a new processor, maybe a new sensor? What video rates would they add? We were all wrong. Sony has unleashed so many upgrades and new technology we have been pretty much blown away. Here’s just a smattering of new features to demonstrate just how much technology they’ve crammed into the new ergonomically shaped body (which still weighs just under 700g.)

Sony a7S III New features at a glance

  • Brand new full-frame back-illuminated Exmor R 12.1MP CMOS sensor
  • New BIONZ XR image processor, which we understand to be up to 8x faster
  • Brand new articulating LCD touchscreen for vlogging and selfies (A first for Sony)
  • New 9.44 Million Dots Quad-XGA OLED EVF
  • Updated easy to navigate menu system (yes Sony do listen!)
  • Upgraded AF for video and stills with 90% coverage from 759 AF points
  • Brand new video codecs XAVC-HS (H.265) and XAVC-S-I (All-I)
  • Upgraded 10-bit 4:2:2 internal recording with 4K video at 120p and 240p HD
  • Wider ISO of 80-102,400 expandable up to ISO 40 - 409,600
  • Dual card slots, cross compatible with new high speed Cfexpress Type A and UHS-II SD
  • 5GHZ wifi connection and full sized HDMI connector (Type-A)
  • 15+ EV stops of dynamic range (the a7R IV has somewhere in the region of 14.77 EV stops).

The list is so long it could indeed pass as a shopping list of everything we would want in a professional photo / video camera, which also manages a blistering 10fps in continuous drive mode. Photographers can blast away in any image combination (including simultaneous uncompressed RAW and JPG) capturing over 1000 images before any buffer warnings.


Sample image in near darkness Sony A7SIII


We’ve put together this table to make it easier to see the specs where Sony has invested in the latest technology for this camera and where it excels over other models in the Sony mirrorless range.

Specs Comparison With The Sony a7S III


a7s II

a7 III

a7R IV






Continuous Shooting







Bionz X

Bionz X

Bionz X

ISO Range

80-102,400 (Expandable 40-409,600)

100-102,400 (Expandable 50-409,600)

100-51,200 (Expandable 50-204,800)

100-32,000 (Expandable 50-102,400)

AF Points





Eye AF





Real Time Eye Tracking





Animal Eye AF





In Body Image Stabilisation

5.5 Stops

4.5 Stops

5 Stops

5.5 Stops

Maximum Video Resolution / Bitrate

4K 10-Bit 4:2:2 Internal

4K 8-Bit 4:2:0 (8-Bit 4:2:2 External)

4K 8-Bit 4:2:0 (8-Bit 4:2:2 External)

4K 8-Bit 4:2:0 (8-Bit 4:2:2 External)

High Frame Rate

4K 120fps / FHD 240fps

FullHD 120fps

FullHD 120fps

FullHD 120fps

S Log

S-Log 2 / S-Log 3

S-Log 2 / S-Log 3

S-Log 2 / S-Log 3

S-Log 2 / S-Log 3

Card Slots

2 x CF Express and UHS II SD cards*

Single UHS-I Card Slot

Dual SD Card Slots UHS II + UHS I

Dual UHS II SD Card Slots


9.44 Million Dots

2.35 Million Dots

2.35 Million Dots

5.76 Million Dots

LCD Screen

Vari Angle Touch Screen

1.22 Million Dot LCD Screen

0.92 Million Dot Touch Screen

1.44 Million Dot Touch Screen

* Sony has announced new Type A CFexpress TOUGH cards which are cross compatible with SD cards for high speed data transfer of up to 700MB/s write speed and 800MB/s read speed. See the new 80GB CF Express card here and the 160GB card here.

Low light, bright light and absolute darkness

One advantage of employing a lower resolution sensor is that low light performance can be extremely competent. A high resolution sensor (such as with the A7r iv) is gathering much more light data into extremely closely packed pixels, whereas the new Exmor R sensor has room to spare, allowing the camera to excel in low light. Incredibly low noise is apparent throughout the range, which is native all the way to ISO 102,400. With a -6EV focus sensitivity this camera is up there at the very summit of dark hour shooting which will appeal to a broad range of users. Astro and night photographers will find the exceptional low light capabilities particularly appealing. Read about other astronomy gear for Jupiter And Saturn in our post here.

Compact and low light photography

12.1 megapixels is more than ample for any digital presentation as well as healthy sized prints for old-skool photographers who still love seeing their work printed out. (Which we recommend by the way). At the other end of the light spectrum, the a7S III lowers native ISO to just 80, which will provide users with smoother images and videos. Speaking of smoother, how about stabilisation?

IBIS and other image stabilisation technologies

It is worth noting that the 5-axis Image Sensor-Shift mechanism is particularly successful when paired with E-mount lenses developed by Sony themselves, taking full advantage of gains up to 5.5 EV stops. These are most apparent with the Sony FE 50mm f/1.4 Zeiss PLANAR T* lens currently, which consistently delivers at this upper level. Stabilisation from sensor shift is lens dependent, however Sony have added other technologies to further assist run and gun photographers and videographers who love to hand-hold. Intelligent active mode adds more stabilisation when recording video with a 1.1x crop and Active Anti Shaking IS has also been included. Whichever way you like to shoot, the a7S III will do its’ best to assist with a range of stabilisation options.

Watch our first look video of the a7S III

Our own videographer Gareth gives viewers a run-through of the a7S III with a first look video here.

The A7S III has an articulating screen - Sonys first ever

Sony forged ahead with leading AF technology through fast, accurate phase-detection and continually make strides to improve their AF system. This includes the number of focus points, sensor coverage, Eye detection and in the last couple of years have started to expand their animal AF capabilities too. The a7S III packs a whopping 759 AF points with 90% coverage and also adds real time tracking for video, making it far easier to keep focus while filming. Once again Sony has delivered with autofocus capabilities which will be welcome by users across the board whether they are shooting video or stills.


“It was a long time coming but we really do believe that the Sony a7S III has such broad ranging upgrades it will make you fall in love with creativity all over again”.

Every aspect of the camera has been updated for 2020 including ergonomics, weather sealing, connectivity and of course video and stills capabilities. Sony content creators who favour movie-making but also require a fast, accurate and low light specialist stills camera need wait no longer. Take an even closer look at the a7S III here on our e-commerce site.

If you crave more pixels, why not read our post on the Sony A7R IV, the world's highest resolution camera.

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By Nick Dautlich on 28/07/2020

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