Sony A7S vs A7S III

The Sony Alpha A7S and the Sony Alpha 7S III are two professional cameras that were officially introduced, respectively, in April 2014 and July 2020. Both the A7S and the A7S III are mirrorless interchangeable lens cameras that are equipped with a full frame sensor. Both cameras offer a resolution of 12 megapixels.

Below is an overview of the main specs of the two cameras as a starting point for the comparison.

Headline Specifications

Sony A7S		Sony A7S III
Mirrorless system camera		Mirrorless system camera
Sony E mount lenses		Sony E mount lenses
12 MP – Full Frame sensor		12 MP – Full Frame sensor
1080/60p Video		4K/120p Video
ISO 100-102,400 (50 - 409,600)		ISO 80-102,400 (40 - 409,600)
Electronic viewfinder (2400k dots)		Electronic viewfinder (9440k dots)
3.0" LCD – 921k dots		3.0" LCD – 1440k dots
Tilting screen (no touchscreen)		Swivel touchscreen
5 shutter flaps per second		10 shutter flaps per second
Lens stabilization only		In-body stabilization
Weathersealed body		Weathersealed body
380 shots per battery charge		600 shots per battery charge
127 x 94 x 48 mm, 489 g		127 x 97 x 81 mm, 699 g

Check A7S offers at
ebay.com
Check A7S III price at
amazon.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Sony Alpha A7S and the Sony Alpha 7S III? Which one should you buy? Read on to find out how these two cameras compare with respect to their body size, their imaging sensors, their shooting features, their input-output connections, and their reception by expert reviewers.

Body comparison

An illustration of the physical size and weight of the Sony A7S and the Sony A7S III is provided in the side-by-side display below. The two cameras are presented according to their relative size. Three successive views from the front, the top, and the rear are shown. All width, height and depth dimensions are rounded to the nearest millimeter.

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony A7S III is somewhat larger (3 percent) than the Sony A7S. Moreover, the A7S III is substantially heavier (43 percent) than the A7S. In this context, it is worth noting that both cameras are splash and dust-proof and can, hence, be used in inclement weather conditions or harsh environments.

The above size and weight comparisons are to some extent incomplete since they do not consider the interchangeable lenses that both of these cameras require. In this particular case, both cameras feature the same lens mount, so that they can use the same lenses. You can compare the optics available in the Sony FE Lens Catalog. Mirrorless cameras, such as the two under consideration, have the additional advantage of having a short flange to focal plane distance, which makes it possible to mount many lenses from other systems onto the camera via adapters.

Concerning battery life, the A7S gets 380 shots out of its Sony NP-FW50 battery, while the A7S III can take 600 images on a single charge of its Sony NP-FZ100 power pack. The battery packs of both cameras can be charged via USB, which can be very convenient when travelling.

The table below summarizes the key physical specs of the two cameras alongside a broader set of comparators. If you want to switch the focus of the display and review another camera pair, you can move across to the CAM-parator tool and choose from the broad selection of possible camera comparisons there.

Body Specifications

		Camera Model	Camera Width	Camera Height	Camera Depth	Camera Weight	Battery Life	Weather Sealing	Camera Launch	Launch Price (USD)	Street Price
1.		Sony A7S	127 mm	94 mm	48 mm	489 g	380	Y	Apr 2014	2,499	ebay.com
2.		Sony A7S III	127 mm	97 mm	81 mm	699 g	600	Y	Jul 2020	3,499	amazon.com
3.		Nikon Df	144 mm	110 mm	67 mm	760 g	1400	Y	Nov 2013	2,749	ebay.com
4.		Sony A7	127 mm	94 mm	48 mm	474 g	340	Y	Oct 2013	1,699	ebay.com
5.		Sony A7 II	127 mm	96 mm	60 mm	599 g	350	Y	Nov 2014	1,999	ebay.com
6.		Sony A7R	127 mm	94 mm	48 mm	465 g	340	Y	Oct 2013	2,299	ebay.com
7.		Sony A7R II	127 mm	96 mm	60 mm	625 g	290	Y	Jun 2015	3,199	ebay.com
8.		Sony A7R III	127 mm	96 mm	74 mm	650 g	650	Y	Oct 2017	3,199	ebay.com
9.		Sony A7R IV	129 mm	96 mm	78 mm	665 g	670	Y	Jul 2019	3,499	ebay.com
10.		Sony A7R IVA	129 mm	96 mm	78 mm	665 g	670	Y	Apr 2021	3,499	amazon.com
11.		Sony A7S II	127 mm	96 mm	60 mm	627 g	370	Y	Sep 2015	2,999	ebay.com
12.		Sony A9 II	129 mm	96 mm	76 mm	678 g	690	Y	Oct 2019	4,499	amazon.com
13.		Sony RX1	113 mm	65 mm	70 mm	482 g	270	n	Sep 2012	2,799	ebay.com
14.		Sony RX1R	113 mm	65 mm	70 mm	482 g	270	n	Jun 2013	2,799	ebay.com
15.		Sony RX1R II	113 mm	65 mm	72 mm	507 g	220	n	Oct 2015	3,299	ebay.com
16.		Sony ZV-E1	121 mm	72 mm	54 mm	483 g	570	Y	Mar 2023	2,199	amazon.com
Note: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.
Convert to Imperial

The price is, of course, an important factor in any camera decision. The retail prices at the time of the camera’s release place the model in the market relative to other models in the producer’s line-up and the competition. The A7S was launched at a markedly lower price (by 29 percent) than the A7S III, which puts it into a different market segment. Usually, retail prices stay at first close to the launch price, but after several months, discounts become available. Later in the product cycle and, in particular, when the replacement model is about to appear, further discounting and stock clearance sales often push the camera price considerably down.

Sensor comparison

The imaging sensor is at the core of digital cameras and its size is one of the main determining factors of image quality. A large sensor will generally have larger individual pixels that offer better low-light sensitivity, provide wider dynamic range, and have richer color-depth than smaller pixels in a sensor of the same technological generation. Moreover, a large sensor camera will give the photographer more control over depth-of-field in the image and, thus, the ability to better isolate a subject from the background. On the downside, larger sensors tend to be more expensive and lead to bigger and heavier cameras and lenses.

Both cameras under consideration feature a full frame sensor, but their sensors differ slightly in size. The sensor area in the A7S III is 1 percent smaller. They nevertheless have the same format factor of 1.0. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.

Technology-wise, the A7S III uses a more advanced image processing engine (BIONZ XR) than the A7S (BIONZ X), with benefits for noise reduction, color accuracy, and processing speed.

Even though the A7S has a slightly larger sensor, both cameras offer the same resolution of 12 megapixels. This implies that the A7S has a lower pixel density and larger individual pixels (with a pixel pitch of 8.45μm versus 8.40μm for the A7S III), which gives it a potential advantage in terms of light gathering capacity. It should, however, be noted that the A7S III is much more recent (by 6 years and 3 months) than the A7S, and its sensor will have benefitted from technological advances during this time that at least partly compensate for the smaller pixel size.

The A7S III has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

The Sony Alpha A7S has a native sensitivity range from ISO 100 to ISO 102400, which can be extended to ISO 50-409600. The corresponding ISO settings for the Sony Alpha 7S III are ISO 80 to ISO 102400, with the possibility to increase the ISO range to 40-409600.

In terms of underlying technology, the A7S is build around a CMOS sensor, while the A7S III uses a BSI-CMOS imager. Both cameras use a Bayer filter for capturing RGB colors on a square grid of photosensors. This arrangement is found in most digital cameras.

Consistent information on actual sensor performance is available from DXO Mark for many cameras. This service assesses and scores the color depth ("DXO Portrait"), dynamic range ("DXO Landscape"), and low-light sensitivity ("DXO Sports") of camera sensors, and also publishes an overall camera score. The Overall DXO ratings for the two cameras under consideration are close, suggesting that they provide similar imaging performance. The table below summarizes the physical sensor characteristics and sensor quality findings and compares them across a set of similar cameras.

Sensor Characteristics

		Camera Model	Sensor Class	Resolution (MP)	Horiz. Pixels	Vert. Pixels	Video Format	DXO Portrait	DXO Landscape	DXO Sports	DXO Overall
1.		Sony A7S	Full Frame	12.0	4240	2832	1080/60p	23.9	13.2	3702	87
2.		Sony A7S III	Full Frame	12.0	4240	2832	4K/120p	23.7	13.9	2520	86
3.		Nikon Df	Full Frame	16.2	4928	3280	none	24.6	13.1	3279	89
4.		Sony A7	Full Frame	24.0	6000	4000	1080/60p	24.8	14.2	2248	90
5.		Sony A7 II	Full Frame	24.0	6000	4000	1080/60p	24.9	13.6	2449	90
6.		Sony A7R	Full Frame	36.2	7360	4912	1080/60p	25.6	14.1	2746	95
7.		Sony A7R II	Full Frame	42.2	7952	5304	4K/30p	26.0	13.9	3434	98
8.		Sony A7R III	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
9.		Sony A7R IV	Full Frame	60.2	9504	6336	4K/30p	26.0	14.8	3344	99
10.		Sony A7R IVA	Full Frame	60.2	9504	6336	4K/30p	26.0	14.8	3344	99
11.		Sony A7S II	Full Frame	12.0	4240	2832	4K/30p	23.6	13.3	2993	85
12.		Sony A9 II	Full Frame	24.0	6000	4000	4K/30p	25.0	14.0	3434	93
13.		Sony RX1	Full Frame	24.0	6000	4000	1080/60p	25.1	14.3	2534	93
14.		Sony RX1R	Full Frame	24.0	6000	4000	1080/60p	25.0	13.6	2537	91
15.		Sony RX1R II	Full Frame	42.2	7952	5304	1080/60p	25.8	13.9	3204	97
16.		Sony ZV-E1	Full Frame	12.0	4240	2832	4K/60p	25.4	14.6	3181	96
Note: DXO values in italics represent estimates based on sensor size and age.

Many modern cameras are not only capable of taking still images, but also of capturing video footage. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, but the A7S III provides a better video resolution than the A7S. It can shoot movie footage at 4K/120p, while the A7S is limited to 1080/60p.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. The two cameras under review are similar with respect to both having an electronic viewfinder. However, the one in the A7S III offers a substantially higher resolution than the one in the A7S (9440k vs 2400k dots). The adjacent table lists some of the other core features of the Sony A7S and Sony A7S III along with similar information for a selection of comparators.

Core Features

		Camera Model	Viewfinder (Type or 000 dots)	Control Panel (yes/no)	LCD Specifications (inch/000 dots)	LCD Attach- ment	Touch Screen (yes/no)	Max Shutter Speed *	Max Shutter Flaps *	Built-in Flash (yes/no)	Built-in Image Stab
1.		Sony A7S	2400	n	3.0 / 921	tilting	n	1/8000s	5.0/s	n	n
2.		Sony A7S III	9440	n	3.0 / 1440	swivel	Y	1/8000s	10.0/s	n	Y
3.		Nikon Df	optical	Y	3.2 / 921	fixed	n	1/4000s	5.5/s	n	n
4.		Sony A7	2400	n	3.0 / 1230	tilting	n	1/8000s	5.0/s	n	n
5.		Sony A7 II	2400	n	3.0 / 1230	tilting	n	1/8000s	5.0/s	n	Y
6.		Sony A7R	2400	n	3.0 / 1230	tilting	n	1/8000s	4.0/s	n	n
7.		Sony A7R II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
8.		Sony A7R III	3686	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
9.		Sony A7R IV	5760	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
10.		Sony A7R IVA	5760	n	3.0 / 2340	tilting	Y	1/8000s	10.0/s	n	Y
11.		Sony A7S II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
12.		Sony A9 II	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
13.		Sony RX1	optional	n	3.0 / 1229	fixed	n	1/4000s	5.0/s	Y	n
14.		Sony RX1R	optional	n	3.0 / 1229	fixed	n	1/4000s	5.0/s	Y	n
15.		Sony RX1R II	2360	n	3.0 / 1229	tilting	n	1/4000s	5.0/s	n	n
16.		Sony ZV-E1	none	n	3.0 / 1037	swivel	Y	1/8000s	10.0/s	n	Y
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One differentiating feature between the two cameras concerns the touch sensitivity of the rear screen. The A7S III has a touchscreen, while the A7S has a conventional panel. Touch control can be particularly helpful, for example, for setting the focus point.

The reported shutter speed information refers to the use of the mechanical shutter. Yet, some cameras only have an electronic shutter, while others have an electronic shutter in addition to a mechanical one. In fact, both cameras under consideration feature an electronic shutter, which makes completely silent shooting possible. However, this mode is less suitable for photographing moving objects (risk of rolling shutter) or shooting under artificial light sources (risk of flickering).

The A7S writes its imaging data to SDXC or Memory Stick PRO Duo cards, while the A7S III uses CFexpress (type A) or SDXC cards. The A7S III features dual card slots, which can be very useful in case a memory card fails. In contrast, the A7S only has one slot. The A7S III supports UHS-II cards (on both slots), while the A7S can use UHS-I cards.

Connectivity comparison

For some imaging applications, the extent to which a camera can communicate with its environment can be an important aspect in the camera decision process. The table below provides an overview of the connectivity of the Sony Alpha A7S and Sony Alpha 7S III and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

Input-Output Connections

		Camera Model	Hotshoe Port	Internal Mic / Speaker	Microphone Port	Headphone Port	HDMI Port	USB Port	WiFi Support	NFC Support	Bluetooth Support
1.		Sony A7S	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
2.		Sony A7S III	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
3.		Nikon Df	Y	- / -	-	-	mini	2.0	-	-	-
4.		Sony A7	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
5.		Sony A7 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
6.		Sony A7R	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
7.		Sony A7R II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
8.		Sony A7R III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
9.		Sony A7R IV	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
10.		Sony A7R IVA	Y	stereo / mono	Y	Y	micro	3.2	Y	Y	Y
11.		Sony A7S II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
12.		Sony A9 II	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
13.		Sony RX1	Y	stereo / mono	Y	-	mini	2.0	-	-	-
14.		Sony RX1R	Y	stereo / mono	Y	-	mini	2.0	-	-	-
15.		Sony RX1R II	Y	stereo / mono	Y	-	micro	2.0	Y	Y	-
16.		Sony ZV-E1	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y

The A7S III is a recent model that features in the current product line-up of Sony. In contrast, the A7S has been discontinued (but can be found pre-owned on ebay). As a replacement in the same line of cameras, the A7S was succeeded by the Sony A7S II. Further information on the features and operation of the A7S and A7S III can be found, respectively, in the Sony A7S Manual (free pdf) or the online Sony A7S III Manual.

Review summary

So what is the bottom line? Is the Sony A7S better than the Sony A7S III or vice versa? Below is a summary of the relative strengths of each of the two contestants.

Advantages of the Sony Alpha A7S:

• Better low-light sensitivity: Requires less light for good images (0.6 stops ISO advantage).
• Less heavy: Is lighter (by 210g or 30 percent) and hence easier to carry around.
• Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
• More affordable: Was introduced into a lower priced category (29 percent cheaper at launch).
• More heavily discounted: Has been available for much longer (launched in April 2014).

Arguments in favor of the Sony Alpha 7S III:

• More dynamic range: Captures a broader range of light and dark details (0.7 EV of extra DR).
• Better jpgs: Has a more modern image processing engine (BIONZ XR vs BIONZ X).
• Better video: Provides higher definition movie capture (4K/120p vs 1080/60p).
• Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
• More detailed viewfinder: Has higher resolution electronic viewfinder (9440k vs 2400k dots).
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.91x vs 0.71x).
• More detailed LCD: Has a higher resolution rear screen (1440k vs 921k dots).
• More flexible LCD: Has a swivel screen for odd-angle shots in portrait or landscape orientation.
• Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Faster burst: Shoots at higher frequency (10 vs 5 flaps/sec) to capture the decisive moment.
• Longer lasting: Gets more shots (600 versus 380) out of a single battery charge.
• Sharper images: Has stabilization technology built-in to reduce the impact of hand-shake.
• Faster data transfer: Supports a more advanced USB protocol (3.2 vs 2.0).
• More solid recording: Has a full-sized HDMI port for a sturdy connection to an external recorder.
• Easier wireless transfer: Supports Bluetooth for image sharing without cables.
• Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
• Faster buffer clearing: Supports a more advanced SD data transfer standard (UHS-II vs UHS-I).
• More modern: Reflects 6 years and 3 months of technical progress since the A7S launch.

If the count of individual advantages (bullet points above) is taken as a guide, the A7S III is the clear winner of the contest (19 : 5 points). However, the relative importance of the various individual camera aspects will vary according to personal preferences and needs, so that you might like to apply corresponding weights to the particular features before making a decision on a new camera. A professional wedding photographer will view the differences between cameras in a way that diverges from the perspective of a travel photog, and a person interested in cityscapes has distinct needs from a macro shooter. Hence, the decision which camera is best and worth buying is often a very personal one.

How about other alternatives? Do the specifications of the Sony A7S and the Sony A7S III place the cameras among the top in their class? Find out in the latest Best Mirrorless Interchangeable Lens Camera listing whether the two cameras rank among the cream of the crop.

In any case, while the specs-based evaluation of cameras can be instructive in revealing their potential as photographic tools, it says little about, for example, the shooting experience and imaging performance of the A7S and the A7S III in practical situations. User reviews that are available, for instance, at amazon can sometimes shed light on these issues, but such feedback is all too often partial, inconsistent, and inaccurate.

Expert reviews

This is why hands-on reviews by experts are important. The adjacent summary-table relays the overall verdicts of several of the most popular camera review sites (amateurphotographer [AP], cameralabs [CL], digitalcameraworld [DCW], dpreview [DPR], ephotozine [EPZ], photographyblog [PB]). As can be seen, the professional reviewers agree in many cases on the quality of different cameras, but sometimes their assessments diverge, reinforcing the earlier point that a camera decision is often a very personal choice.

Expert Camera Reviews

		Camera   Model	AP   score	CL   score	DCW   score	DPR   score	EPZ   score	PB   score	Camera Launch	Launch Price (USD)	Street Price
1.		Sony A7S	4/5	..	..	86/100	4.5/5	5/5	Apr 2014	2,499	ebay.com
2.		Sony A7S III	4.5/5	+ +	5/5	91/100	4.5/5	5/5	Jul 2020	3,499	amazon.com
3.		Nikon Df	4/5	..	..	81/100	4/5	4/5	Nov 2013	2,749	ebay.com
4.		Sony A7	5/5	+ +	..	80/100	5/5	5/5	Oct 2013	1,699	ebay.com
5.		Sony A7 II	5/5	+	4/5	82/100	4.5/5	5/5	Nov 2014	1,999	ebay.com
6.		Sony A7R	5/5	+ +	..	82/100	4.5/5	5/5	Oct 2013	2,299	ebay.com
7.		Sony A7R II	5/5	+ +	5/5	90/100	5/5	5/5	Jun 2015	3,199	ebay.com
8.		Sony A7R III	..	+ +	4/5	90/100	4.5/5	5/5	Oct 2017	3,199	ebay.com
9.		Sony A7R IV	5/5	+	4.5/5	91/100	4.5/5	5/5	Jul 2019	3,499	ebay.com
10.		Sony A7R IVA	5/5	+	4.5/5	91/100	4.5/5	5/5	Apr 2021	3,499	amazon.com
11.		Sony A7S II	5/5	+	..	..	4.5/5	5/5	Sep 2015	2,999	ebay.com
12.		Sony A9 II	..	..	5/5	90/100	5/5	5/5	Oct 2019	4,499	amazon.com
13.		Sony RX1	5/5	..	..	79/100	4/5	4.5/5	Sep 2012	2,799	ebay.com
14.		Sony RX1R	5/5	..	..	..	4/5	4.5/5	Jun 2013	2,799	ebay.com
15.		Sony RX1R II	5/5	..	..	82/100	..	4.5/5	Oct 2015	3,299	ebay.com
16.		Sony ZV-E1	..	+	4/5	..	..	4.5/5	Mar 2023	2,199	amazon.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

Care should be taken when interpreting the review scores above, though. The assessments were made in relation to similar cameras of the same technological generation. A score, therefore, has to be seen in close connection to the price and market introduction time of the camera, and comparing ratings of very distinct cameras or ones that are far apart in terms of their release date have little meaning. It should also be noted that some of the review sites have over time altered the way they render their verdicts.

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Check A7S III price at
amazon.com

Other camera comparisons

Did this review help to inform your camera decision process? In case you would like to check on the differences and similarities of other camera models, just use the search menu below. As an alternative, you can also directly jump to any one of the listed comparisons that were previously generated by the CAM-parator tool.

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