Canon G3 X vs Sony A7S

The Canon PowerShot G3 X and the Sony Alpha A7S are two digital cameras that were officially introduced, respectively, in June 2015 and April 2014. The G3X is a fixed lens compact, while the A7S is a mirrorless interchangeable lens camera. The cameras are based on an one-inch (G3X) and a full frame (A7S) sensor. The Canon has a resolution of 20 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 G3 X		Sony A7S
Fixed lens compact camera		Mirrorless system camera
24-600mm f/2.8-5.6		Sony E mount lenses
20 MP – 1" sensor		12 MP – Full Frame sensor
1080/60p Video		1080/60p Video
ISO 125-12,800 (125 - 25,600)		ISO 100-102,400 (50 - 409,600)
Viewfinder optional		Electronic viewfinder (2400k dots)
3.2" LCD – 1620k dots		3.0" LCD – 921k dots
Tilting touchscreen		Tilting screen (no touchscreen)
5.9 shutter flaps per second		5 shutter flaps per second
Weathersealed body		Weathersealed body
300 shots per battery charge		380 shots per battery charge
123 x 77 x 105 mm, 733 g		127 x 94 x 48 mm, 489 g

Check G3X offers at
ebay.com
Check A7S offers at
ebay.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Canon PowerShot G3 X and the Sony Alpha A7S? 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 side-by-side display below illustrates the physical size and weight of the Canon G3 X and the Sony A7S. 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 A7S is notably larger (26 percent) than the Canon G3 X. 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 and possibly misleading, as the G3X has a lens built in, whereas the A7S is an interchangeable lens camera that requires a separate lens. Attaching the latter will add extra weight and bulk to the setup. You can compare the optics available for the A7S and their specifications in the Sony FE Lens Catalog.

Concerning battery life, the G3X gets 300 shots out of its Canon NB-10L battery, while the A7S can take 380 images on a single charge of its Sony NP-FW50 power pack. The power pack in the A7S 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 G3 X	123 mm	77 mm	105 mm	733 g	300	Y	Jun 2015	999	ebay.com
2.		Sony A7S	127 mm	94 mm	48 mm	489 g	380	Y	Apr 2014	2,499	ebay.com
3.		Canon 80D	139 mm	105 mm	79 mm	730 g	960	Y	Feb 2016	1,199	ebay.com
4.		Canon G9 X	98 mm	58 mm	31 mm	209 g	220	n	Oct 2015	529	ebay.com
5.		Canon G7 X	103 mm	60 mm	40 mm	304 g	210	n	Sep 2014	699	ebay.com
6.		Canon 70D	139 mm	104 mm	79 mm	755 g	920	Y	Jul 2013	1,199	ebay.com
7.		Nikon Df	144 mm	110 mm	67 mm	760 g	1400	Y	Nov 2013	2,749	ebay.com
8.		Panasonic FZ2500	138 mm	102 mm	135 mm	915 g	350	n	Sep 2016	1,199	amazon.com
9.		Panasonic FZ1000	137 mm	99 mm	131 mm	831 g	360	n	Jun 2014	899	ebay.com
10.		Sony ZV-E1	121 mm	72 mm	54 mm	483 g	570	Y	Mar 2023	2,199	amazon.com
11.		Sony RX10 III	133 mm	94 mm	127 mm	1051 g	420	Y	Mar 2016	1,499	ebay.com
12.		Sony RX100 V	102 mm	58 mm	41 mm	299 g	220	n	Oct 2016	999	ebay.com
13.		Sony A7S II	127 mm	96 mm	60 mm	627 g	370	Y	Sep 2015	2,999	ebay.com
14.		Sony RX10 II	129 mm	88 mm	102 mm	813 g	400	Y	Jun 2015	1,299	ebay.com
15.		Sony A7	127 mm	94 mm	48 mm	474 g	340	Y	Oct 2013	1,699	ebay.com
16.		Sony A7R	127 mm	94 mm	48 mm	465 g	340	Y	Oct 2013	2,299	ebay.com
17.		Sony RX10	129 mm	88 mm	102 mm	813 g	420	Y	Oct 2013	1,299	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 manufacturer’s suggested retail prices give an idea on the placement of the camera in the maker’s lineup and the broader market. The G3X was launched at a lower price than the A7S, despite having a lens built in. 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 size of the imaging sensor is a crucial determinant 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. 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.

Of the two cameras under consideration, the Canon G3 X features an one-inch sensor and the Sony A7S a full frame sensor. The sensor area in the A7S is 638 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 2.7 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 G3 X offers a higher resolution of 20 megapixels, compared with 12 MP of the Sony A7S. 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 2.41μm versus 8.45μm for the A7S). However, it should be noted that the G3X is a somewhat more recent model (by 1 year and 2 months) than the A7S, and its sensor might have benefitted from technological advances during this time that partly offset its pixel-size disadvantage.

The resolution advantage of the Canon G3 X implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the G3X for good quality output (200 dots per inch) amounts to 27.4 x 18.2 inches or 69.5 x 46.3 cm, for very good quality (250 dpi) 21.9 x 14.6 inches or 55.6 x 37.1 cm, and for excellent quality (300 dpi) 18.2 x 12.2 inches or 46.3 x 30.9 cm. The corresponding values for the Sony A7S 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 PowerShot G3 X has a native sensitivity range from ISO 125 to ISO 12800, which can be extended to ISO 125-25600. The corresponding ISO settings for the Sony Alpha A7S are ISO 100 to ISO 102400, with the possibility to increase the ISO range to 50-409600.

In terms of underlying technology, the G3X is build around a BSI-CMOS sensor, while the A7S uses a 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.

Since 2007, DXO Mark has published sensor performance measurements that have been derived using a consistent methodology. This service is based on lab testing and assigns an overall score to each camera sensor, as well as ratings for dynamic range ("DXO Landscape"), color depth ("DXO Portrait"), and low-light sensitivity ("DXO Sports"). Of the two cameras under consideration, the A7S offers substantially better image quality than the G3X (overall score 24 points higher). The advantage is based on 2.5 bits higher color depth, 0.9 EV in additional dynamic range, and 2.8 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 G3 X	1-inch	20.0	5472	3648	1080/60p	21.4	12.3	521	63
2.		Sony A7S	Full Frame	12.0	4240	2832	1080/60p	23.9	13.2	3702	87
3.		Canon 80D	APS-C	24.0	6000	4000	1080/60p	23.6	13.2	1135	79
4.		Canon G9 X	1-inch	20.0	5472	3648	1080/60p	21.5	12.3	495	63
5.		Canon G7 X	1-inch	20.0	5472	3648	1080/60p	23.0	12.7	556	71
6.		Canon 70D	APS-C	20.0	5472	3648	1080/30p	22.5	11.6	926	68
7.		Nikon Df	Full Frame	16.2	4928	3280	none	24.6	13.1	3279	89
8.		Panasonic FZ2500	1-inch	20.0	5472	3648	4K/30p	23.0	12.6	538	70
9.		Panasonic FZ1000	1-inch	20.0	5472	3648	4K/30p	22.1	11.7	517	64
10.		Sony ZV-E1	Full Frame	12.0	4240	2832	4K/60p	25.4	14.6	3181	96
11.		Sony RX10 III	1-inch	20.0	5472	3648	4K/30p	23.1	12.6	472	70
12.		Sony RX100 V	1-inch	20.0	5472	3648	4K/30p	22.8	12.4	586	70
13.		Sony A7S II	Full Frame	12.0	4240	2832	4K/30p	23.6	13.3	2993	85
14.		Sony RX10 II	1-inch	20.0	5472	3648	4K/30p	23.0	12.6	531	70
15.		Sony A7	Full Frame	24.0	6000	4000	1080/60p	24.8	14.2	2248	90
16.		Sony A7R	Full Frame	36.2	7360	4912	1080/60p	25.6	14.1	2746	95
17.		Sony RX10	1-inch	20.0	5472	3648	1080/60p	22.9	12.6	474	69
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 are equipped with sensors that have a sufficiently high read-out speed for moving images, and both provide the same movie specifications (1080/60p).

Feature comparison

Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A7S has an electronic viewfinder (2400k dots), which can be very helpful when shooting in bright sunlight. In contrast, the G3X relies on live view and the rear LCD for framing. That said, the G3X can be equipped with an optional viewfinder – the EVF-DC1. The adjacent table lists some of the other core features of the Canon G3 X and Sony A7S 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.		Canon G3 X	optional	n	3.2 / 1620	tilting	Y	1/2000s	5.9/s	Y	Y
2.		Sony A7S	2400	n	3.0 / 921	tilting	n	1/8000s	5.0/s	n	n
3.		Canon 80D	optical	Y	3.0 / 1040	swivel	Y	1/8000s	7.0/s	Y	n
4.		Canon G9 X	none	n	3.0 / 1040	fixed	Y	1/2000s	6.0/s	Y	Y
5.		Canon G7 X	none	n	3.0 / 1040	tilting	Y	1/2000s	6.5/s	Y	Y
6.		Canon 70D	optical	Y	3.0 / 1040	swivel	Y	1/8000s	7.0/s	Y	n
7.		Nikon Df	optical	Y	3.2 / 921	fixed	n	1/4000s	5.5/s	n	n
8.		Panasonic FZ2500	2360	n	3.0 / 1040	swivel	Y	1/4000s	12.0/s	Y	Y
9.		Panasonic FZ1000	2359	n	3.0 / 921	swivel	n	1/4000s	12.0/s	Y	Y
10.		Sony ZV-E1	none	n	3.0 / 1037	swivel	Y	1/8000s	10.0/s	n	Y
11.		Sony RX10 III	2359	Y	3.0 / 1229	tilting	n	1/2000s	14.0/s	Y	Y
12.		Sony RX100 V	2359	n	3.0 / 1229	tilting	n	1/2000s	24.0/s	Y	Y
13.		Sony A7S II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
14.		Sony RX10 II	2359	Y	3.0 / 1229	tilting	n	1/3200s	14.0/s	Y	Y
15.		Sony A7	2400	n	3.0 / 1230	tilting	n	1/8000s	5.0/s	n	n
16.		Sony A7R	2400	n	3.0 / 1230	tilting	n	1/8000s	4.0/s	n	n
17.		Sony RX10	1440	Y	3.0 / 1229	tilting	n	1/3200s	10.0/s	Y	Y
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One difference between the cameras concerns the presence of an on-board flash. The G3X has one, while the A7S does not. While the built-in flash of the G3X is not very powerful, it can at times be useful as a fill-in light.

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 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 G3X writes its imaging data to SDXC cards, while the A7S uses SDXC or Memory Stick PRO Duo cards. Both cameras can use UHS-I cards, which provide for Ultra High Speed data transfer of up to 104 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 Canon PowerShot G3 X and Sony Alpha A7S 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 G3 X	Y	stereo / mono	Y	Y	mini	2.0	Y	Y	-
2.		Sony A7S	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
3.		Canon 80D	Y	stereo / mono	Y	Y	mini	2.0	Y	Y	-
4.		Canon G9 X	-	stereo / mono	-	-	micro	2.0	Y	Y	-
5.		Canon G7 X	-	stereo / mono	-	-	micro	2.0	Y	Y	-
6.		Canon 70D	Y	stereo / mono	Y	-	mini	2.0	Y	-	-
7.		Nikon Df	Y	- / -	-	-	mini	2.0	-	-	-
8.		Panasonic FZ2500	Y	stereo / mono	Y	Y	micro	2.0	Y	-	-
9.		Panasonic FZ1000	Y	stereo / mono	Y	-	micro	2.0	Y	Y	-
10.		Sony ZV-E1	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
11.		Sony RX10 III	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
12.		Sony RX100 V	-	stereo / mono	-	-	micro	2.0	Y	Y	-
13.		Sony A7S II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
14.		Sony RX10 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
15.		Sony A7	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
16.		Sony A7R	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
17.		Sony RX10	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-

Both the G3X and the A7S have been discontinued, but can regularly be found used on ebay. The A7S was replaced by the Sony A7S II, while the G3X does not have a direct successor. Further information on the features and operation of the G3X and A7S can be found, respectively, in the Canon G3 X Manual (free pdf) or the online Sony A7S Manual.

Review summary

So what conclusions can be drawn? Is there a clear favorite between the Canon G3 X and the Sony A7S? Which camera is better? A synthesis of the relative strong points of each of the models is listed below.

Arguments in favor of the Canon PowerShot G3 X:

• More detail: Offers more megapixels (20 vs 12MP) with a 29% higher linear resolution.
• Larger screen: Has a bigger rear LCD (3.2" vs 3.0") for image review and settings control.
• More detailed LCD: Has a higher resolution rear screen (1620k vs 921k dots).
• Fewer buttons to press: Is equipped with a touch-sensitive rear screen to facilitate handling.
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Faster burst: Shoots at higher frequency (5.9 vs 5 flaps/sec) to capture the decisive moment.
• Ready to shoot: Has a lens built-in, whereas the A7S requires a separate lens.
• More compact: Is smaller (123x77mm vs 127x94mm) and thus needs less room in the bag.
• Sharper images: Has hand-shake reducing image stabilization built-in.
• Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
• More affordable: Was introduced at a lower price, despite coming with a built-in lens.
• More modern: Is somewhat more recent (announced 1 year and 2 months after the A7S).

Advantages of the Sony Alpha A7S:

• Better image quality: Scores substantially higher (24 points) in the DXO overall evaluation.
• Richer colors: Generates noticeably more natural colors (2.5 bits more color depth).
• More dynamic range: Captures a broader range of light and dark details (0.9 EV of extra DR).
• Better low-light sensitivity: Can shoot in dim conditions (2.8 stops ISO advantage).
• Easier framing: Has an electronic viewfinder for image composition and settings control.
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/2000s) to freeze action.
• Less disturbing: Has an electronic shutter option for completely silent shooting.
• More flexible: Takes interchangeable lenses and can thus be used with specialty optics.
• Longer lasting: Gets more shots (380 versus 300) out of a single battery charge.
• Easier travel charging: Can be conveniently charged via its USB port.
• More heavily discounted: Has been on the market for longer (launched in April 2014).

If the count of individual advantages (bullet points above) is taken as a guide, the G3X comes out slightly ahead of the A7S (12 : 11 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 Canon G3 X and the Sony A7S place the cameras among the top in their class? Find out in the latest Best Superzoom Camera and Best Mirrorless Interchangeable Lens Camera listings whether the two cameras rank among the cream of the crop.

In any case, while the comparison of technical specifications can provide a useful overview of the capabilities of different cameras, it remains incomplete and does no justice, for example, to the way the G3X or the A7S perform in practice. At times, user reviews, such as those published at amazon, address these issues in a useful manner, but such feedback is on many occasions incomplete, inconsistent, and unreliable.

Expert reviews

This is why hands-on reviews by experts are important. The table below provides a synthesis of the camera assessments of some of the best known photo-gear 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 G3 X	3.5/5	+	..	..	4.5/5	4/5	Jun 2015	999	ebay.com
2.		Sony A7S	4/5	..	..	86/100	4.5/5	5/5	Apr 2014	2,499	ebay.com
3.		Canon 80D	4/5	+ +	4.5/5	84/100	4.5/5	4.5/5	Feb 2016	1,199	ebay.com
4.		Canon G9 X	3.5/5	+ +	..	..	4.5/5	4.5/5	Oct 2015	529	ebay.com
5.		Canon G7 X	4/5	+ +	..	77/100	4.5/5	4.5/5	Sep 2014	699	ebay.com
6.		Canon 70D	5/5	+ +	..	83/100	4.5/5	5/5	Jul 2013	1,199	ebay.com
7.		Nikon Df	4/5	..	..	81/100	4/5	4/5	Nov 2013	2,749	ebay.com
8.		Panasonic FZ2500	..	+	..	82/100	4.5/5	5/5	Sep 2016	1,199	amazon.com
9.		Panasonic FZ1000	4/5	+ +	..	82/100	4.5/5	4.5/5	Jun 2014	899	ebay.com
10.		Sony ZV-E1	..	+	4/5	..	..	4.5/5	Mar 2023	2,199	amazon.com
11.		Sony RX10 III	5/5	+	..	84/100	4.5/5	4.5/5	Mar 2016	1,499	ebay.com
12.		Sony RX100 V	4.5/5	+ +	..	83/100	4/5	4.5/5	Oct 2016	999	ebay.com
13.		Sony A7S II	5/5	+	..	..	4.5/5	5/5	Sep 2015	2,999	ebay.com
14.		Sony RX10 II	5/5	+ +	..	82/100	4.5/5	4/5	Jun 2015	1,299	ebay.com
15.		Sony A7	5/5	+ +	..	80/100	5/5	5/5	Oct 2013	1,699	ebay.com
16.		Sony A7R	5/5	+ +	..	82/100	4.5/5	5/5	Oct 2013	2,299	ebay.com
17.		Sony RX10	5/5	+	..	80/100	4.5/5	4.5/5	Oct 2013	1,299	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

The above review scores should be interpreted with care, though. The ratings are only valid when referring to cameras in the same category and of the same age. 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.

Check G3X offers at
ebay.com
Check A7S offers at
ebay.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.

~

Check G3X offers at
ebay.com
Check A7S offers at
ebay.com

Did you notice an error on this page? If so, please get in touch, so that we can correct the information.