Panasonic S1 II vs Sony A9 III

The Panasonic Lumix DC-S1 II and the Sony Alpha A9 III are two digital cameras that were revealed to the public, respectively, in May 2025 and November 2023. Both the S1 II and the A9 III are mirrorless interchangeable lens cameras that are equipped with a full frame sensor. Both cameras offer a resolution of 24 megapixels.

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

Headline Specifications

Panasonic S1 II		Sony A9 III
Mirrorless system camera		Mirrorless system camera
Leica L mount lenses		Sony E mount lenses
24 MP – Full Frame sensor		24 MP – Full Frame sensor
6K/30p Video		4K/120p Video
ISO 100-51,200 (50 - 204,800)		ISO 250-25,600 (125 - 51,200)
Electronic viewfinder (5760k dots)		Electronic viewfinder (9440k dots)
3.2" LCD – 1840k dots		3.2" LCD – 2100k dots
Fully flexible touchscreen		Fully flexible touchscreen
10 shutter flaps per second		120 shutter flaps per second
In-body stabilization		In-body stabilization
Weathersealed body		Weathersealed body
350 shots per battery charge		530 shots per battery charge
134 x 102 x 92 mm, 800 g		136 x 97 x 83 mm, 702 g

Check S1 II price at
amazon.com
Check A9 III price at
amazon.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Panasonic Lumix DC-S1 II and the Sony Alpha A9 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 Panasonic S1 II and the Sony A9 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 size 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 A9 III is somewhat smaller (3 percent) than the Panasonic S1 II. Moreover, the A9 III is markedly lighter (12 percent) than the S1 II. 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. Hence, you might want to study and compare the specifications of available lenses in order to get the full picture of the size and weight of the two camera systems.

Concerning battery life, the S1 II gets 350 shots out of its Panasonic DMW-BLK22 battery, while the A9 III can take 530 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	Street Price
1.		Panasonic S1 II	134 mm	102 mm	92 mm	800 g	350	Y	May 2025	US$ 3 199	amazon.com
2.		Sony A9 III	136 mm	97 mm	83 mm	702 g	530	Y	Nov 2023	US$ 5 999	amazon.com
3.		Leica SL2-S	146 mm	107 mm	83 mm	931 g	510	Y	Dec 2020	US$ 4 899	amazon.com
4.		Leica SL3	141 mm	108 mm	85 mm	854 g	320	Y	Mar 2024	US$ 6 999	amazon.com
5.		Leica SL3-S	141 mm	108 mm	85 mm	852 g	315	Y	Jan 2025	US$ 5 299	amazon.com
6.		Panasonic GH7	138 mm	100 mm	100 mm	805 g	380	Y	Jun 2024	US$ 2 199	amazon.com
7.		Panasonic S1	149 mm	110 mm	97 mm	1017 g	400	Y	Feb 2019	US$ 2 499	ebay.com
8.		Panasonic S1H	151 mm	114 mm	110 mm	1052 g	400	Y	May 2019	US$ 3 999	amazon.com
9.		Panasonic S1R II	134 mm	102 mm	92 mm	795 g	350	Y	May 2025	US$ 3 299	amazon.com
10.		Panasonic S5	133 mm	98 mm	82 mm	714 g	440	Y	Sep 2020	US$ 1 999	amazon.com
11.		Panasonic S5 II	134 mm	102 mm	90 mm	740 g	370	Y	Jan 2023	US$ 1 999	amazon.com
12.		Panasonic S9	126 mm	74 mm	47 mm	486 g	470	n	May 2024	US$ 1 499	amazon.com
13.		Sony A1 II	136 mm	97 mm	83 mm	743 g	520	Y	Nov 2024	US$ 6 499	amazon.com
14.		Sony A7 II	127 mm	96 mm	60 mm	599 g	350	Y	Nov 2014	US$ 1 999	ebay.com
15.		Sony A7 III	127 mm	96 mm	74 mm	650 g	610	Y	Feb 2018	US$ 1 999	amazon.com
16.		Sony A9	127 mm	96 mm	63 mm	673 g	650	Y	Apr 2017	US$ 4 499	ebay.com
17.		Sony A9 II	129 mm	96 mm	76 mm	678 g	690	Y	Oct 2019	US$ 4 499	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 manufacturer’s suggested retail prices give an idea on the placement of the camera in the maker’s lineup and the broader market. The S1 II was launched at a markedly lower price (by 47 percent) than the A9 III, which puts it into a different market segment. Normally, street prices remain initially close to the MSRP, but after a couple of months, the first discounts appear. 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 size of the imaging sensor is a crucial determinant of image quality. A large sensor will tend to have larger individual pixels that provide better low-light sensitivity, wider dynamic range, and richer color-depth than smaller pixel-units in a sensor of the same technological generation. Further, a large sensor camera will give the photographer additional creative options when using shallow depth-of-field to isolate a subject from its 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 A9 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.

Even though the S1 II has a slightly larger sensor, both cameras offer the same resolution of 24 megapixels. This implies that the S1 II has a lower pixel density and larger individual pixels (with a pixel pitch of 5.97μm versus 5.94μm for the A9 III), which gives it a potential advantage in terms of light gathering capacity. In addition, the S1 II is a somewhat more recent model (by 1 year and 6 months) than the A9 III, and its sensor might have benefitted from technological advances during this time. Coming back to sensor resolution, it should be mentioned that the S1 II has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

Unlike the A9 III, the S1 II has the capacity to capture high quality composite images (96MP) by combining multiple shots after shifting its sensor by miniscule distances. This multi-shot, pixel-shift mode is most suitable for photography of stationary objects (landscapes, studio scenes).

The Panasonic Lumix DC-S1 II has a native sensitivity range from ISO 100 to ISO 51200, which can be extended to ISO 50-204800. The corresponding ISO settings for the Sony Alpha A9 III are ISO 250 to ISO 25600, with the possibility to increase the ISO range to 125-51200.

In terms of underlying technology, the S1 II is build around a BSI-CMOS sensor, while the A9 III uses a Stacked 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 determines an overall sensor rating, as well as sub-scores for low-light sensitivity ("DXO Sports"), dynamic range ("DXO Landscape"), and color depth ("DXO Portrait"). The following table provides an overview of the physical sensor characteristics, as well as the sensor quality measurements for a selection of comparators.

Sensor Characteristics

		Camera Model	Sensor Class	Resolution (MP)	Horiz. Pixels	Vert. Pixels	Video Format	DXO Portrait	DXO Landscape	DXO Sports	DXO Overall
1.		Panasonic S1 II	Full Frame	24.0	6000	4000	6K/30p	25.4	14.8	3406	97
2.		Sony A9 III	Full Frame	24.0	6000	4000	4K/120p	25.4	14.7	3243	96
3.		Leica SL2-S	Full Frame	24.0	6000	4000	4K/60p	25.2	14.1	3504	95
4.		Leica SL3	Full Frame	60.3	9520	6336	8K/30p	25.4	14.8	3295	97
5.		Leica SL3-S	Full Frame	24.0	6000	4000	6K/30p	25.4	14.8	3383	97
6.		Panasonic GH7	Four Thirds	25.0	5776	4336	5.7K/60p	23.4	13.6	1784	78
7.		Panasonic S1	Full Frame	24.0	6000	4000	4K/60p	25.2	14.5	3333	95
8.		Panasonic S1H	Full Frame	24.0	6000	4000	6K/30p	25.2	14.2	2805	94
9.		Panasonic S1R II	Full Frame	44.2	8144	5424	8K/30p	25.4	14.8	3406	97
10.		Panasonic S5	Full Frame	24.0	6000	4000	4K/60p	25.1	14.5	2697	94
11.		Panasonic S5 II	Full Frame	24.0	6000	4000	6K/30p	25.4	14.6	3158	96
12.		Panasonic S9	Full Frame	24.0	6000	4000	6K/30p	25.4	14.8	3297	96
13.		Sony A1 II	Full Frame	49.8	8640	5760	8k/30p	25.4	14.8	3363	97
14.		Sony A7 II	Full Frame	24.0	6000	4000	1080/60p	24.9	13.6	2449	90
15.		Sony A7 III	Full Frame	24.0	6000	4000	4K/30p	25.0	14.7	3730	96
16.		Sony A9	Full Frame	24.0	6000	4000	4K/30p	24.9	13.3	3517	92
17.		Sony A9 II	Full Frame	24.0	6000	4000	4K/30p	25.0	14.0	3434	93
Note: DXO values in italics represent estimates based on sensor size and age.

Many modern cameras cannot only take still pictures, but also record videos. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, but the S1 II provides a higher video resolution than the A9 III. It can shoot video footage at 6K/30p, while the Sony is limited to 4K/120p.

Feature comparison

Apart from 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 A9 III offers a substantially higher resolution than the one in the S1 II (9440k vs 5760k dots). The table below summarizes some of the other core capabilities of the Panasonic S1 II and Sony A9 III in connection with corresponding information for a sample of similar cameras.

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.		Panasonic S1 II	5760	n	3.2 / 1840	full-flex	Y	1/8000s	10.0/s	n	Y
2.		Sony A9 III	9440	n	3.2 / 2100	full-flex	Y	1/80000s	120.0/s	n	Y
3.		Leica SL2-S	5760	Y	3.2 / 2100	fixed	Y	1/8000s	20.0/s	n	Y
4.		Leica SL3	5760	Y	3.2 / 2333	tilting	Y	1/8000s	5.0/s	n	Y
5.		Leica SL3-S	5760	Y	3.2 / 2333	tilting	Y	1/8000s	30.0/s	n	Y
6.		Panasonic GH7	3680	n	3.0 / 1840	full-flex	Y	1/8000s	14.0/s	n	Y
7.		Panasonic S1	5760	Y	3.2 / 2100	full-flex	Y	1/8000s	9.0/s	n	Y
8.		Panasonic S1H	5760	Y	3.2 / 2330	swivel	Y	1/8000s	9.0/s	n	Y
9.		Panasonic S1R II	5760	n	3.2 / 1840	full-flex	Y	1/8000s	9.0/s	n	Y
10.		Panasonic S5	2360	n	3.0 / 1840	swivel	Y	1/8000s	7.0/s	n	Y
11.		Panasonic S5 II	3680	n	3.0 / 1840	swivel	Y	1/8000s	9.0/s	n	Y
12.		Panasonic S9	none	n	3.0 / 1840	swivel	Y	1/8000s	30.0/s	n	Y
13.		Sony A1 II	9437	n	3.2 / 2100	full-flex	Y	1/8000s	30.0/s	n	Y
14.		Sony A7 II	2400	n	3.0 / 1230	tilting	n	1/8000s	5.0/s	n	Y
15.		Sony A7 III	2359	n	3.0 / 922	tilting	Y	1/8000s	10.0/s	n	Y
16.		Sony A9	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
17.		Sony A9 II	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

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 Panasonic S1 II and the Sony A9 III both have an intervalometer built-in. This enables the photographer to capture time lapse sequences, such as flower blooming, a sunset or moon rise, without purchasing an external camera trigger and related software.

The S1 II writes its imaging data to CFexpress (type B) or SDXC cards, while the A9 III uses CFexpress (type A) or SDXC cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. Both cameras support UHS-II cards, which provide for Ultra High Speed data transfer of up to 312 MB/s.

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 Panasonic Lumix DC-S1 II and Sony Alpha A9 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.		Panasonic S1 II	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
2.		Sony A9 III	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
3.		Leica SL2-S	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
4.		Leica SL3	Y	stereo / mono	Y	Y	full	3.1	Y	-	Y
5.		Leica SL3-S	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
6.		Panasonic GH7	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
7.		Panasonic S1	Y	stereo / mono	Y	Y	full	3.1	Y	-	Y
8.		Panasonic S1H	Y	stereo / mono	Y	Y	full	3.1	Y	-	Y
9.		Panasonic S1R II	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
10.		Panasonic S5	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
11.		Panasonic S5 II	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
12.		Panasonic S9	Y	stereo / mono	Y	-	micro	3.2	Y	-	Y
13.		Sony A1 II	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
14.		Sony A7 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
15.		Sony A7 III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
16.		Sony A9	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	Y
17.		Sony A9 II	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y

Both cameras feature a PC Sync terminal to control professional strobe lights, which will be appreciated by studio photographers.

Both the S1 II and the A9 III are recent models that are part of the current product line-up. The A9 III replaced the earlier Sony A9 II, while the S1 II followed on from the Panasonic S1. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Panasonic and Sony websites.

Review summary

So what is the bottom line? Is there a clear favorite between the Panasonic S1 II and the Sony A9 III? Which camera is better? The listing below highlights the relative strengths of the two models.

Advantages of the Panasonic Lumix DC-S1 II:

• Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
• High quality composites: Can combine several shots after pixel-shifting its sensor.
• Better video: Provides higher definition movie capture (6K/30p vs 4K/120p).
• More affordable: Was introduced into a lower priced category (47 percent cheaper at launch).
• More modern: Is somewhat more recent (announced 1 year and 6 months after the A9 III).

Reasons to prefer the Sony Alpha A9 III:

• Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
• More detailed viewfinder: Has higher resolution electronic viewfinder (9440k vs 5760k dots).
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.9x vs 0.78x).
• More detailed LCD: Has a higher resolution rear screen (2100k vs 1840k dots).
• Faster shutter: Has higher mechanical shutter speed (1/80000s vs 1/8000s) to freeze action.
• Faster burst: Shoots at higher frequency (120 vs 10 flaps/sec) to capture the decisive moment.
• Less heavy: Has a lower weight (by 98g or 12 percent) and is thus easier to take along.
• Longer lasting: Gets more shots (530 versus 350) out of a single battery charge.
• More heavily discounted: Has been on the market for longer (launched in November 2023).

If the count of individual advantages (bullet points above) is taken as a guide, the A9 III is the clear winner of the contest (9 : 5 points). However, the pertinence of the various camera strengths will differ across photographers, so that you might want to weigh individual camera traits according to their importance for your own imaging needs before making a camera decision. A professional wildlife photographer will view the differences between cameras in a way that diverges from the perspective of a family photog, and a person interested in architecture has distinct needs from a sports 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 Panasonic S1 II and the Sony A9 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 comparison of the spec-sheets of cameras can offer a general idea of their imaging potential, it remains incomplete and does no justice, for example, to the way the S1 II or the A9 III perform in practice. 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 where reviews by experts come in. 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	Street Price
1.		Panasonic S1 II	..	..	..	..	..	..	May 2025	US$ 3 199	amazon.com
2.		Sony A9 III	4.5/5	..	..	91/100	..	..	Nov 2023	US$ 5 999	amazon.com
3.		Leica SL2-S	4/5	..	4/5	..	4.5/5	4.5/5	Dec 2020	US$ 4 899	amazon.com
4.		Leica SL3	..	..	4.5/5	..	..	4.5/5	Mar 2024	US$ 6 999	amazon.com
5.		Leica SL3-S	..	..	..	..	..	..	Jan 2025	US$ 5 299	amazon.com
6.		Panasonic GH7	..	..	..	..	..	..	Jun 2024	US$ 2 199	amazon.com
7.		Panasonic S1	4.5/5	+ +	4.5/5	88/100	4.5/5	4/5	Feb 2019	US$ 2 499	ebay.com
8.		Panasonic S1H	..	..	4/5	90/100	..	..	May 2019	US$ 3 999	amazon.com
9.		Panasonic S1R II	..	..	..	..	..	..	May 2025	US$ 3 299	amazon.com
10.		Panasonic S5	4.5/5	+ +	4.5/5	88/100	4.5/5	4.5/5	Sep 2020	US$ 1 999	amazon.com
11.		Panasonic S5 II	4.5/5	+ +	5/5	90/100	4.5/5	5/5	Jan 2023	US$ 1 999	amazon.com
12.		Panasonic S9	..	..	..	..	..	..	May 2024	US$ 1 499	amazon.com
13.		Sony A1 II	..	..	..	..	..	..	Nov 2024	US$ 6 499	amazon.com
14.		Sony A7 II	5/5	+	4/5	82/100	4.5/5	5/5	Nov 2014	US$ 1 999	ebay.com
15.		Sony A7 III	..	+ +	4.5/5	89/100	5/5	5/5	Feb 2018	US$ 1 999	amazon.com
16.		Sony A9	5/5	+ +	4.8/5	89/100	5/5	5/5	Apr 2017	US$ 4 499	ebay.com
17.		Sony A9 II	..	..	5/5	90/100	5/5	5/5	Oct 2019	US$ 4 499	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 comparisons of ratings among very different cameras or across long time periods have little meaning. Also, please note that some of the review sites have changed their methodology and reporting over time.

Check S1 II price at
amazon.com
Check A9 III price at
amazon.com

Other camera comparisons

Did this review help to inform your camera decision process? In case you are interested in seeing how other cameras pair up, just make a corresponding selection in the search boxes below. Alternatively, you can follow any of the listed hyperlinks for comparisons that others found interesting.

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Check S1 II price at
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Check A9 III price at
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