DxOMark published their Sony a7S III sensor review and test results – Sony a7S III’s 12.1MP full-frame exmor R BSI sensor achieved an excellent overall score of 86 points (just 1 point above the Sony a7S II), with a combination of 23.7 bits color depth, 13.9 EV dynamic range, and 2520 ISO low-light score.
With the overall score of 86 points, Sony A7S III has the 53rd position in the database of full-frame 35 mm and MF sensors overall, the 51st place for full-frame 35 mm, and the 17th place for Sony cameras.
Conclusion from DxOMark:
The Sony A7S III leverages a lot of tech from the A7 and A7R models, and its stills credentials are impressive. However, 12 MP is considered a bit on the low side for stills nowadays, and it is principally as a video camera that the Sony A7S III appeals. The lower pixel count means the sensor’s pixel dimensions on the long edge deliver essentially native 4K without cropping, and those large pixels should have benefits when working with less than ideal lighting.
Although it puts in a strong performance at its lowest ISO settings, with a relatively high maximum dynamic range and maximum color sensitivity, evidently some concessions were made in that regard, as it is at high ISOs where it’s class-leading. In particular, the Sony A7S III sensor has an impressive response between ISO 1600 and ISO 6400, even outperforming rivals using 24 MP BSI CMOS sensors.
Whether that’s enough to entice dedicated stills photographers is debatable, given the price, but videographers are likely to be attracted by the benefits it brings in post-production, especially when working in S-Log. With excellent high ISO image quality, small size, low weight, and a built-in stabilizer, the Sony A7S III is highly appealing as a versatile hand-held camera for single operators or small production crews.
Sony a7S III is the best mirrorless camera for video, and almost everything else. Sony’s 12.1-megapixel A7S III was worth the five-year wait. It has the same incredible low-light capability of its predecessors, but adds much-needed features like improved stabilization, a flip-out touch display and 4K video at up to 120 fps. The camera can record 4K video at 10-bit 4:2:2 internally, has up to 600mbps recording, and supports dual SD UHS-II or new CFexpress Type-A cards.
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