Canon M vs Sony A7S III

The Canon EOS M and the Sony Alpha 7S III are two digital cameras that were officially introduced, respectively, in July 2012 and July 2020. Both the Canon M and the A7S III are mirrorless interchangeable lens cameras that are based on an APS-C (Canon M) and a full frame (A7S III) sensor. The Canon has a resolution of 17.9 megapixels, whereas the Sony provides 12 MP.

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

Headline Specifications

Canon M		Sony A7S III
Mirrorless system camera		Mirrorless system camera
Canon EF-M mount lenses		Sony E mount lenses
17.9 MP – APS-C sensor		12 MP – Full Frame sensor
1080/30p Video		4K/120p Video
ISO 100-12,800 (100 - 25,600)		ISO 80-102,400 (40 - 409,600)
No viewfinder, LCD framing		Electronic viewfinder (9440k dots)
3.0" LCD – 1040k dots		3.0" LCD – 1440k dots
Fixed touchscreen		Swivel touchscreen
4.3 shutter flaps per second		10 shutter flaps per second
Lens stabilization only		In-body stabilization
not weather sealed		Weathersealed body
230 shots per battery charge		600 shots per battery charge
109 x 66 x 32 mm, 298 g		127 x 97 x 81 mm, 699 g

Check Canon M 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 Canon EOS M 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

The physical size and weight of the Canon M and the Sony A7S III are illustrated in the side-by-side display below. The two cameras are presented according to their relative size. Three consecutive perspectives from the front, the top, and the back are available. All width, height and depth dimensions are rounded to the nearest millimeter.

The Canon M can be obtained in two different colors (black, white), while the A7S III is only available in black.

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 considerably larger (71 percent) than the Canon M. Moreover, the A7S III is substantially heavier (135 percent) than the Canon M. It is noteworthy in this context that the A7S III is splash and dust-proof, while the Canon M does not feature any corresponding weather-sealing.

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 Canon M gets 230 shots out of its Canon LP-E12 battery, while the A7S III can take 600 images on a single charge of its Sony NP-FZ100 power pack. The power pack in the A7S III can be charged via the USB port, 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 would like to visualize and compare a different camera combination, you can navigate to the CAM-parator app and make your selection from a broad list of cameras 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.		Canon M	109 mm	66 mm	32 mm	298 g	230	n	Jul 2012	599	ebay.com
2.		Sony A7S III	127 mm	97 mm	81 mm	699 g	600	Y	Jul 2020	3,499	amazon.com
3.		Canon G7 X	103 mm	60 mm	40 mm	304 g	210	n	Sep 2014	699	ebay.com
4.		Canon G16	109 mm	76 mm	40 mm	356 g	360	n	Aug 2013	549	ebay.com
5.		Canon M10	108 mm	67 mm	35 mm	301 g	255	n	Oct 2015	499	ebay.com
6.		Canon M100	108 mm	67 mm	35 mm	302 g	295	n	Aug 2017	499	ebay.com
7.		Canon SL1	117 mm	91 mm	69 mm	407 g	380	n	Mar 2013	549	ebay.com
8.		Canon T3i	133 mm	100 mm	80 mm	570 g	440	n	Feb 2011	599	ebay.com
9.		Canon T5i	133 mm	100 mm	79 mm	580 g	440	n	Mar 2013	649	ebay.com
10.		Panasonic G3	115 mm	84 mm	47 mm	336 g	270	n	May 2011	599	ebay.com
11.		Panasonic GF6	111 mm	65 mm	38 mm	323 g	340	n	Apr 2013	499	ebay.com
12.		Sony A7R III	127 mm	96 mm	74 mm	650 g	650	Y	Oct 2017	3,199	ebay.com
13.		Sony A7R IV	129 mm	96 mm	78 mm	665 g	670	Y	Jul 2019	3,499	ebay.com
14.		Sony A7R IVA	129 mm	96 mm	78 mm	665 g	670	Y	Apr 2021	3,499	amazon.com
15.		Sony A7S II	127 mm	96 mm	60 mm	627 g	370	Y	Sep 2015	2,999	ebay.com
16.		Sony A9 II	129 mm	96 mm	76 mm	678 g	690	Y	Oct 2019	4,499	amazon.com
17.		Sony NEX-3N	110 mm	62 mm	35 mm	269 g	480	n	Feb 2013	499	ebay.com
Note: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.
Convert to Imperial

Any camera decision will naturally be influenced heavily by the price. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The Canon M was launched at a markedly lower price (by 83 percent) than the A7S 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. Then, after the new model is out, very good deals can frequently be found on the pre-owned market.

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. All other things equal, a large sensor will have larger individual pixel-units that offer better low-light sensitivity, wider dynamic range, and 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 are more costly to manufacture and tend to lead to bigger and heavier cameras and lenses.

Of the two cameras under consideration, the Canon M features an APS-C sensor and the Sony A7S III a full frame sensor. The sensor area in the A7S III is 155 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.6 and 1.0. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.

Despite having a smaller sensor, the Canon M offers a higher resolution of 17.9 megapixels, compared with 12 MP of the Sony A7S III. This megapixels advantage comes at the cost of a higher pixel density and a smaller size of the individual pixel (with a pixel pitch of 4.31μm versus 8.40μm for the A7S III). Moreover, it should be noted that the A7S III is much more recent (by 8 years) than the Canon M, and its sensor will have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixel-units.

The resolution advantage of the Canon M implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the Canon M for good quality output (200 dots per inch) amounts to 25.9 x 17.3 inches or 65.8 x 43.9 cm, for very good quality (250 dpi) 20.7 x 13.8 inches or 52.7 x 35.1 cm, and for excellent quality (300 dpi) 17.3 x 11.5 inches or 43.9 x 29.3 cm. The corresponding values for the Sony A7S III are 21.2 x 14.2 inches or 53.8 x 36 cm for good quality, 17 x 11.3 inches or 43.1 x 28.8 cm for very good quality, and 14.1 x 9.4 inches or 35.9 x 24 cm for excellent quality prints.

The Canon EOS M has a native sensitivity range from ISO 100 to ISO 12800, which can be extended to ISO 100-25600. 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 Canon M 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.

For many cameras, data on sensor performance has been reported by DXO Mark. 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. Of the two cameras under consideration, the A7S III offers substantially better image quality than the Canon M (overall score 21 points higher). The advantage is based on 1.6 bits higher color depth, 2.7 EV in additional dynamic range, and 1.6 stops in additional low light sensitivity. 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.		Canon M	APS-C	17.9	5184	3456	1080/30p	22.1	11.2	827	65
2.		Sony A7S III	Full Frame	12.0	4240	2832	4K/120p	23.7	13.9	2520	86
3.		Canon G7 X	1-inch	20.0	5472	3648	1080/60p	23.0	12.7	556	71
4.		Canon G16	1/1.7	12.0	4000	3000	1080/60p	21.0	11.7	230	54
5.		Canon M10	APS-C	17.9	5184	3456	1080/30p	22.2	11.4	753	65
6.		Canon M100	APS-C	24.0	6000	4000	1080/60p	23.5	12.9	1272	78
7.		Canon SL1	APS-C	17.9	5184	3456	1080/30p	21.8	11.3	843	63
8.		Canon T3i	APS-C	17.9	5184	3456	1080/30p	22.1	11.5	793	65
9.		Canon T5i	APS-C	17.9	5184	3456	1080/30p	21.7	11.2	681	61
10.		Panasonic G3	Four Thirds	15.8	4592	3448	1080/60i	21.0	10.6	667	56
11.		Panasonic GF6	Four Thirds	15.8	4592	3448	1080/60i	20.7	10.6	622	54
12.		Sony A7R III	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
13.		Sony A7R IV	Full Frame	60.2	9504	6336	4K/30p	26.0	14.8	3344	99
14.		Sony A7R IVA	Full Frame	60.2	9504	6336	4K/30p	26.0	14.8	3344	99
15.		Sony A7S II	Full Frame	12.0	4240	2832	4K/30p	23.6	13.3	2993	85
16.		Sony A9 II	Full Frame	24.0	6000	4000	4K/30p	25.0	14.0	3434	93
17.		Sony NEX-3N	APS-C	16.0	4912	3264	1080/60i	22.8	12.5	1067	74

Many modern cameras are not only capable of taking still images, but can also record movies. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, but the A7S III provides a better video resolution than the Canon M. It can shoot movie footage at 4K/120p, while the Canon is limited to 1080/30p.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. For example, the A7S III has an electronic viewfinder (9440k dots), which can be very helpful when shooting in bright sunlight. In contrast, the Canon M relies on live view and the rear LCD for framing. The following table reports on some other key feature differences and similarities of the Canon M, the Sony A7S III, and comparable 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.		Canon M	none	n	3.0 / 1040	fixed	Y	1/4000s	4.3/s	n	n
2.		Sony A7S III	9440	n	3.0 / 1440	swivel	Y	1/8000s	10.0/s	n	Y
3.		Canon G7 X	none	n	3.0 / 1040	tilting	Y	1/2000s	6.5/s	Y	Y
4.		Canon G16	optical	n	3.0 / 922	fixed	n	1/4000s	2.2/s	Y	Y
5.		Canon M10	none	n	3.0 / 1040	tilting	Y	1/4000s	4.6/s	Y	n
6.		Canon M100	none	n	3.0 / 1040	tilting	Y	1/4000s	6.1/s	Y	n
7.		Canon SL1	optical	n	3.0 / 1040	fixed	Y	1/4000s	4.9/s	Y	n
8.		Canon T3i	optical	n	3.0 / 1040	swivel	n	1/4000s	3.7/s	Y	n
9.		Canon T5i	optical	n	3.0 / 1040	swivel	Y	1/4000s	5.0/s	Y	n
10.		Panasonic G3	1440	n	3.0 / 460	swivel	Y	1/4000s	4.0/s	Y	n
11.		Panasonic GF6	none	n	3.0 / 1040	tilting	Y	1/4000s	4.2/s	Y	n
12.		Sony A7R III	3686	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
13.		Sony A7R IV	5760	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
14.		Sony A7R IVA	5760	n	3.0 / 2340	tilting	Y	1/8000s	10.0/s	n	Y
15.		Sony A7S II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
16.		Sony A9 II	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
17.		Sony NEX-3N	optional	n	3.0 / 460	tilting	n	1/4000s	4.0/s	Y	n
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One feature that differentiates the A7S III and the Canon M is in-body image stabilization (IBIS). The A7S III reduces the risk of handshake-induced blur with all attached lenses, while the Canon M offers no blur reduction with lenses that themselves do not provide optical image stabilization.

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, the A7S III is one of those camera that have an additional 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 Canon M writes its imaging data to SDXC 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 Canon M only has one slot. The A7S III supports UHS-II cards (on both slots), while the Canon M 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 Canon EOS M 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.		Canon M	Y	stereo / mono	Y	-	mini	2.0	-	-	-
2.		Sony A7S III	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
3.		Canon G7 X	-	stereo / mono	-	-	micro	2.0	Y	Y	-
4.		Canon G16	Y	stereo / mono	-	-	mini	2.0	Y	-	-
5.		Canon M10	-	stereo / mono	-	-	mini	2.0	Y	Y	-
6.		Canon M100	-	stereo / mono	-	-	micro	2.0	Y	Y	Y
7.		Canon SL1	Y	mono / mono	Y	-	mini	2.0	-	-	-
8.		Canon T3i	Y	mono / mono	Y	-	mini	2.0	-	-	-
9.		Canon T5i	Y	stereo / mono	Y	-	mini	2.0	-	-	-
10.		Panasonic G3	Y	stereo / mono	-	-	mini	2.0	-	-	-
11.		Panasonic GF6	-	stereo / mono	-	-	mini	2.0	Y	Y	-
12.		Sony A7R III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
13.		Sony A7R IV	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
14.		Sony A7R IVA	Y	stereo / mono	Y	Y	micro	3.2	Y	Y	Y
15.		Sony A7S II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
16.		Sony A9 II	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
17.		Sony NEX-3N	-	stereo / mono	-	-	micro	2.0	-	-	-

It is notable that the A7S III offers wifi support, which can be a very convenient means to transfer image data to an off-camera location. In contrast, the Canon M does not provide wifi capability.

The A7S III is a recent model that features in the current product line-up of Sony. In contrast, the Canon M has been discontinued (but can be found pre-owned on ebay). As a replacement in the same line of cameras, the Canon M was succeeded by the Canon EOS M3. Further information on the features and operation of the Canon M and A7S III can be found, respectively, in the Canon M Manual (free pdf) or the online Sony A7S III Manual.

Review summary

So what is the bottom line? Is there a clear favorite between the Canon M and the Sony A7S III? Which camera is better? Below is a summary of the relative strengths of each of the two contestants.

Reasons to prefer the Canon EOS M:

• More detail: Offers more megapixels (17.9 vs 12MP) with a 22% higher linear resolution.
• More compact: Is smaller (109x66mm vs 127x97mm) and thus needs less room in the bag.
• Less heavy: Is lighter (by 401g or 57 percent) and hence easier to carry around.
• More affordable: Was introduced into a lower priced category (83 percent cheaper at launch).
• More heavily discounted: Has been available for much longer (launched in July 2012).

Arguments in favor of the Sony Alpha 7S III:

• Better image quality: Scores substantially higher (21 points) in the DXO overall evaluation.
• Richer colors: Generates noticeably more natural colors (1.6 bits more color depth).
• More dynamic range: Captures a broader range of light and dark details (2.7 EV of extra DR).
• Better low-light sensitivity: Can shoot in dim conditions (1.6 stops ISO advantage).
• Better video: Provides higher definition movie capture (4K/120p vs 1080/30p).
• Better sound control: Has a headphone port that enables audio monitoring while recording.
• Easier framing: Has an electronic viewfinder for image composition and settings control.
• More detailed LCD: Has a higher resolution rear screen (1440k vs 1040k dots).
• More flexible LCD: Has a swivel screen for odd-angle shots in portrait or landscape orientation.
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
• Faster burst: Shoots at higher frequency (10 vs 4.3 flaps/sec) to capture the decisive moment.
• Less disturbing: Has an electronic shutter option for completely silent shooting.
• Longer lasting: Gets more shots (600 versus 230) out of a single battery charge.
• Easier travel charging: Can be conveniently charged via its USB port.
• Better sealing: Is splash and dust sealed for shooting in inclement weather conditions.
• 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).
• Easier file upload: Has wifi built in for automatic backup or image transfer to the web.
• 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 8 years of technical progress since the Canon M launch.

If the count of relative strengths (bullet points above) is taken as a measure, the A7S III is the clear winner of the contest (24 : 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 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 Canon M 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 comparison of the spec-sheets of cameras can offer a general idea of their imaging potential, it remains partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the Canon M or the A7S III. 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 (USD)	Street Price
1.		Canon M	3/5	+	..	..	4/5	4/5	Jul 2012	599	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.		Canon G7 X	4/5	+ +	..	77/100	4.5/5	4.5/5	Sep 2014	699	ebay.com
4.		Canon G16	4/5	+	..	..	4.5/5	4.5/5	Aug 2013	549	ebay.com
5.		Canon M10	..	..	..	..	..	4/5	Oct 2015	499	ebay.com
6.		Canon M100	3/5	+	..	..	4/5	3.5/5	Aug 2017	499	ebay.com
7.		Canon SL1	4/5	+	..	78/100	4/5	4/5	Mar 2013	549	ebay.com
8.		Canon T3i	3/5	o	..	77/100	4.5/5	4.5/5	Feb 2011	599	ebay.com
9.		Canon T5i	..	..	..	76/100	4.5/5	4.5/5	Mar 2013	649	ebay.com
10.		Panasonic G3	3/5	+ +	..	75/100	4.5/5	5/5	May 2011	599	ebay.com
11.		Panasonic GF6	..	+ +	..	..	4.5/5	4.5/5	Apr 2013	499	ebay.com
12.		Sony A7R III	..	+ +	4/5	90/100	4.5/5	5/5	Oct 2017	3,199	ebay.com
13.		Sony A7R IV	5/5	+	4.5/5	91/100	4.5/5	5/5	Jul 2019	3,499	ebay.com
14.		Sony A7R IVA	5/5	+	4.5/5	91/100	4.5/5	5/5	Apr 2021	3,499	amazon.com
15.		Sony A7S II	5/5	+	..	..	4.5/5	5/5	Sep 2015	2,999	ebay.com
16.		Sony A9 II	..	..	5/5	90/100	5/5	5/5	Oct 2019	4,499	amazon.com
17.		Sony NEX-3N	3/5	..	..	..	4.5/5	4.5/5	Feb 2013	499	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

The above review scores should be interpreted with care, though. The assessments were made in relation to similar cameras of the same technological generation. Hence, a score should always be seen in the context of the camera's market launch date and its price, and comparing ratings of very distinct cameras or ones that are far apart in terms of their release date have little meaning. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

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amazon.com

Other camera comparisons

Did this review help to inform your camera decision process? If you would like to see a different side-by-side camera review, just use the search menu below. There is also a set of direct links to comparison reviews that other users of the CAM-parator app explored.

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