Canon G7 X Mark III vs Pentax K-S2

The Canon PowerShot G7 X Mark III and the Pentax K-S2 are two digital cameras that were revealed to the public, respectively, in July 2019 and February 2015. The G7X Mark III is a fixed lens compact, while the K-S2 is a DSLR. The cameras are based on an one-inch (G7X Mark III) and an APS-C (K-S2) sensor. Both cameras offer a resolution of 20 megapixels.

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

Headline Specifications

Canon G7 X Mark III		Pentax K-S2
Fixed lens compact camera		Digital single lens reflex
24-100mm f/1.8-2.8		Pentax K mount lenses
20 MP – 1" sensor		20 MP – APS-C sensor
4K/30p Video		1080/30p Video
ISO 125-12,800 (125 - 25,600)		ISO 100-51,200
No viewfinder, LCD framing		Optical viewfinder
3.0" LCD – 1040k dots		3.0" LCD – 921k dots
Tilting touchscreen		Swivel screen (not touch-sensitive)
30 shutter flaps per second		5.4 shutter flaps per second
Lens-based stabilization		In-body stabilization
not weather sealed		Weathersealed body
235 shots per battery charge		410 shots per battery charge
105 x 61 x 41 mm, 304 g		123 x 91 x 73 mm, 678 g

Check G7X Mark III price at
amazon.com
Check K-S2 offers at
ebay.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Canon PowerShot G7 X Mark III and the Pentax K-S2? 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 G7 X Mark III and the Pentax K-S2 are illustrated 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.

The G7X Mark III can be obtained in two different colors (black, silver), while the K-S2 is available in six color-versions (black, grey, pink, orange, green, white).

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Pentax K-S2 is considerably larger (75 percent) than the Canon G7 X Mark III. It is noteworthy in this context that the K-S2 is splash and dust-proof, while the G7X Mark III does not feature any corresponding weather-sealing.

The above size and weight comparisons are to some extent incomplete and possibly misleading, as the G7X Mark III has a lens built in, whereas the K-S2 is an interchangeable lens camera that requires a separate lens. Attaching the latter will add extra weight and bulk to the setup.

Concerning battery life, the G7X Mark III gets 235 shots out of its Canon NB-13L battery, while the K-S2 can take 410 images on a single charge of its Pentax D-LI109 power pack. The power pack in the G7X Mark III can be charged via the USB port, so that it is not always necessary to take the battery charger along when travelling.

The following table provides a synthesis of the main physical specifications of the two cameras and other similar ones. 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 G7 X Mark III	105 mm	61 mm	41 mm	304 g	235	n	Jul 2019	749	amazon.com
2.		Pentax K-S2	123 mm	91 mm	73 mm	678 g	410	Y	Feb 2015	749	ebay.com
3.		Canon G5 X	112 mm	76 mm	44 mm	353 g	210	n	Oct 2015	799	ebay.com
4.		Canon G5 X Mark II	111 mm	61 mm	46 mm	340 g	230	n	Jul 2019	899	ebay.com
5.		Canon G7 X	103 mm	60 mm	40 mm	304 g	210	n	Sep 2014	699	ebay.com
6.		Canon G7 X Mark II	106 mm	61 mm	42 mm	319 g	265	n	Feb 2016	699	ebay.com
7.		Canon M50	116 mm	88 mm	59 mm	390 g	235	n	Feb 2018	779	ebay.com
8.		Canon SX740	110 mm	64 mm	40 mm	299 g	265	n	Jul 2018	399	amazon.com
9.		Fujifilm XF10	113 mm	64 mm	41 mm	279 g	330	n	Jul 2018	499	ebay.com
10.		Panasonic TZ200	111 mm	65 mm	45 mm	340 g	370	n	Feb 2018	799	amazon.com
11.		Pentax K-3	131 mm	100 mm	77 mm	800 g	560	Y	Oct 2013	1,299	ebay.com
12.		Pentax K-3 II	131 mm	100 mm	77 mm	800 g	720	Y	Apr 2015	1,099	ebay.com
13.		Pentax K-70	126 mm	93 mm	74 mm	688 g	410	Y	Jun 2016	649	ebay.com
14.		Pentax KP	132 mm	101 mm	76 mm	703 g	390	Y	Jan 2017	1,099	ebay.com
15.		Pentax K-S1	121 mm	93 mm	70 mm	558 g	410	n	Aug 2014	749	ebay.com
16.		Sony RX100 VI	102 mm	58 mm	43 mm	301 g	240	n	Jun 2018	1,199	ebay.com
17.		Sony ZV-1	105 mm	60 mm	44 mm	294 g	260	n	May 2020	799	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

The price is, of course, an important factor in any camera decision. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. 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 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. Furthermore, a large sensor camera will give the photographer more possibilities to use shallow depth-of-field in order to 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 G7 X Mark III features an one-inch sensor and the Pentax K-S2 an APS-C sensor. The sensor area in the K-S2 is 216 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 2.7 and 1.5. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.

Even though the K-S2 has a larger sensor, both cameras offer the same resolution of 20 megapixels. This implies that the K-S2 has a lower pixel density and larger individual pixels (with a pixel pitch of 4.28μm versus 2.41μm for the G7X Mark III), which gives it a potential advantage in terms of light gathering capacity. It should, however, be noted that the G7X Mark III is much more recent (by 4 years and 4 months) than the K-S2, and its sensor will have benefitted from technological advances during this time that at least partly compensate for the smaller pixel size. Coming back to sensor resolution, it should be mentioned that the K-S2 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The Canon PowerShot G7 X Mark III 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 Pentax K-S2 are ISO 100 to ISO 51200 (no boost).

In terms of underlying technology, the G7X Mark III is build around a BSI-CMOS sensor, while the K-S2 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.

Consistent information on actual sensor performance is available from DXO Mark for many cameras. 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"). The adjacent table reports on the physical sensor characteristics and the outcomes of the DXO sensor quality tests for a sample of comparator-cameras.

Sensor Characteristics

		Camera Model	Sensor Class	Resolution (MP)	Horiz. Pixels	Vert. Pixels	Video Format	DXO Portrait	DXO Landscape	DXO Sports	DXO Overall
1.		Canon G7 X Mark III	1-inch	20.0	5472	3648	4K/30p	22.2	12.4	583	65
2.		Pentax K-S2	APS-C	20.0	5472	3648	1080/30p	23.6	12.9	1514	79
3.		Canon G5 X	1-inch	20.0	5472	3648	1080/60p	21.4	12.3	471	62
4.		Canon G5 X Mark II	1-inch	20.0	5472	3648	4K/30p	22.2	12.4	583	65
5.		Canon G7 X	1-inch	20.0	5472	3648	1080/60p	23.0	12.7	556	71
6.		Canon G7 X Mark II	1-inch	20.0	5472	3648	1080/60p	21.8	11.9	260	62
7.		Canon M50	APS-C	24.0	6000	4000	4K/24p	23.8	13.3	1684	81
8.		Canon SX740	1/2.3	20.2	5184	3888	4K/30p	20.6	12.1	1050	51
9.		Fujifilm XF10	APS-C	24.0	6000	4000	4K/15p	24.0	13.4	1844	83
10.		Panasonic TZ200	1-inch	20.0	5472	3648	4K/30p	22.0	12.2	449	64
11.		Pentax K-3	APS-C	24.1	6016	4000	1080/60i	23.7	13.4	1216	80
12.		Pentax K-3 II	APS-C	24.1	6016	4000	1080/60i	23.6	13.6	1106	80
13.		Pentax K-70	APS-C	24.0	6000	4000	1080/60i	23.8	13.1	1639	80
14.		Pentax KP	APS-C	24.1	6016	4000	1080/60i	23.9	13.2	1699	81
15.		Pentax K-S1	APS-C	20.0	5472	3648	1080/30p	23.5	13.0	1061	78
16.		Sony RX100 VI	1-inch	20.0	5472	3648	4K/30p	22.1	12.3	478	64
17.		Sony ZV-1	1-inch	20.0	5472	3648	4K/30p	22.2	12.6	669	66
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 G7X Mark III provides a higher video resolution than the K-S2. It can shoot video footage at 4K/30p, while the Pentax is limited to 1080/30p.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. For example, the K-S2 has an optical viewfinder, which can be very useful when shooting in bright sunlight. In contrast, the G7X Mark III relies on live view and the rear LCD for framing. The adjacent table lists some of the other core features of the Canon G7 X Mark III and Pentax K-S2 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 G7 X Mark III	none	n	3.0 / 1040	tilting	Y	1/2000s	30/s	Y	Y
2.		Pentax K-S2	optical	n	3.0 / 921	swivel	n	1/6000s	5.4/s	Y	Y
3.		Canon G5 X	2360	n	3.0 / 1040	swivel	Y	1/2000s	5.9/s	Y	Y
4.		Canon G5 X Mark II	2360	n	3.0 / 1040	tilting	Y	1/2000s	30/s	Y	Y
5.		Canon G7 X	none	n	3.0 / 1040	tilting	Y	1/2000s	6.5/s	Y	Y
6.		Canon G7 X Mark II	none	n	3.0 / 1040	tilting	Y	1/2000s	8.0/s	Y	Y
7.		Canon M50	2360	n	3.0 / 1040	swivel	Y	1/4000s	10.0/s	Y	n
8.		Canon SX740	none	n	3.0 / 922	tilting	n	1/3200s	10.0/s	Y	Y
9.		Fujifilm XF10	none	n	3.0 / 1040	fixed	Y	1/4000s	6.0/s	Y	n
10.		Panasonic TZ200	2330	n	3.0 / 1240	fixed	Y	1/2000s	10.0/s	Y	Y
11.		Pentax K-3	optical	Y	3.2 / 1037	fixed	n	1/8000s	8.3/s	Y	Y
12.		Pentax K-3 II	optical	Y	3.2 / 1037	fixed	n	1/8000s	8.3/s	n	Y
13.		Pentax K-70	optical	n	3.0 / 921	swivel	n	1/6000s	6.0/s	Y	Y
14.		Pentax KP	optical	n	3.0 / 921	tilting	n	1/6000s	7.0/s	Y	Y
15.		Pentax K-S1	optical	n	3.0 / 921	fixed	n	1/6000s	5.4/s	Y	Y
16.		Sony RX100 VI	2359	n	3.0 / 1229	tilting	Y	1/2000s	24.0/s	Y	Y
17.		Sony ZV-1	none	n	3.0 / 922	swivel	Y	1/2000s	24.0/s	n	n
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 G7X Mark III has a touchscreen, while the K-S2 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, the G7X Mark 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 G7 X Mark III and the Pentax K-S2 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.

Concerning the storage of imaging data, both the G7X Mark III and the K-S2 write their files to SDXC 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 G7 X Mark III and Pentax K-S2 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 G7 X Mark III	-	stereo / mono	Y	-	micro	3.1	Y	-	Y
2.		Pentax K-S2	Y	mono / mono	Y	-	micro	2.0	Y	Y	-
3.		Canon G5 X	Y	stereo / mono	-	-	mini	2.0	Y	Y	-
4.		Canon G5 X Mark II	-	stereo / mono	-	-	micro	3.1	Y	-	Y
5.		Canon G7 X	-	stereo / mono	-	-	micro	2.0	Y	Y	-
6.		Canon G7 X Mark II	-	stereo / mono	-	-	micro	2.0	Y	Y	-
7.		Canon M50	Y	stereo / mono	Y	-	micro	2.0	Y	-	Y
8.		Canon SX740	-	stereo / mono	-	-	micro	2.0	Y	-	Y
9.		Fujifilm XF10	-	stereo / mono	Y	-	micro	2.0	Y	-	Y
10.		Panasonic TZ200	-	stereo / mono	-	-	micro	2.0	Y	-	Y
11.		Pentax K-3	Y	mono / mono	Y	Y	mini	3.0	-	-	-
12.		Pentax K-3 II	Y	mono / mono	Y	Y	mini	3.0	-	-	-
13.		Pentax K-70	Y	stereo / mono	Y	-	mini	2.0	Y	-	-
14.		Pentax KP	Y	stereo / mono	Y	-	-	2.0	Y	-	-
15.		Pentax K-S1	Y	stereo / mono	-	-	micro	2.0	-	-	-
16.		Sony RX100 VI	-	stereo / mono	-	-	micro	2.0	Y	Y	Y
17.		Sony ZV-1	Y	stereo / mono	Y	-	micro	2.0	Y	-	Y

It is notable that the K-S2 has a hotshoe, which makes it possible to easily attach optional accessories, such as an external flash gun. The G7X Mark III does not feature such an accessory-socket.

The G7X Mark III is a recent model that features in the current product line-up of Canon. In contrast, the K-S2 has been discontinued (but can be found pre-owned on ebay). There has not been a direct replacement model for the K-S2 from Pentax. Further information on the features and operation of the G7X Mark III and K-S2 can be found, respectively, in the Canon G7 X Mark III Manual (free pdf) or the online Pentax K-S2 Manual.

Review summary

So how do things add up? Is there a clear favorite between the Canon G7 X Mark III and the Pentax K-S2? Which camera is better? The listing below highlights the relative strengths of the two models.

Arguments in favor of the Canon PowerShot G7 X Mark III:

• Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
• Better video: Provides higher definition movie capture (4K/30p vs 1080/30p).
• More detailed LCD: Has a higher resolution rear screen (1040k vs 921k dots).
• Fewer buttons to press: Is equipped with a touch-sensitive rear screen to facilitate handling.
• Faster burst: Shoots at higher frequency (30 vs 5.4 flaps/sec) to capture the decisive moment.
• Less disturbing: Has an electronic shutter option for completely silent shooting.
• Ready to shoot: Comes with a built-in lens, while the K-S2 requires a separate lens.
• More compact: Is smaller (105x61mm vs 123x91mm) and thus needs less room in the bag.
• Less heavy: Is lighter even though it comes with a built-in lens (unlike the K-S2).
• Easier travel charging: Can be conveniently charged via its USB port.
• Faster data transfer: Supports a more advanced USB protocol (3.1 vs 2.0).
• Easier wireless transfer: Supports Bluetooth for image sharing without cables.
• More modern: Reflects 4 years and 4 months of technical progress since the K-S2 launch.

Advantages of the Pentax K-S2:

• Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
• Easier framing: Has an optical viewfinder for image composition and settings control.
• More flexible LCD: Has a swivel screen for odd-angle shots in portrait or landscape orientation.
• Faster shutter: Has higher mechanical shutter speed (1/6000s vs 1/2000s) to freeze action.
• More flexible: Makes it possible to change lenses and thus to use specialty optics.
• Longer lasting: Gets more shots (410 versus 235) out of a single battery charge.
• Better sealing: Is splash and dust sealed for shooting in inclement weather conditions.
• Better lighting: Features a hotshoe and can thus hold and trigger an external flash gun.
• Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
• More heavily discounted: Has been around for much longer (launched in February 2015).

If the number of relative strengths (bullet points above) is taken as a guide, the G7X Mark III emerges as the winner of the contest (13 : 10 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 G7 X Mark III and the Pentax K-S2 place the cameras among the top in their class? Find out in the latest Best Travel-Zoom Camera and Best DSLR 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 partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the G7X Mark III or the K-S2. 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.		Canon G7 X Mark III	..	+ +	4/5	81/100	4/5	..	Jul 2019	749	amazon.com
2.		Pentax K-S2	4.5/5	..	..	..	5/5	4.5/5	Feb 2015	749	ebay.com
3.		Canon G5 X	5/5	+ +	..	78/100	4.5/5	4.5/5	Oct 2015	799	ebay.com
4.		Canon G5 X Mark II	4/5	+	4/5	82/100	..	4/5	Jul 2019	899	ebay.com
5.		Canon G7 X	4/5	+ +	..	77/100	4.5/5	4.5/5	Sep 2014	699	ebay.com
6.		Canon G7 X Mark II	4.5/5	+ +	..	81/100	4.5/5	4.5/5	Feb 2016	699	ebay.com
7.		Canon M50	..	+	4/5	79/100	..	3.5/5	Feb 2018	779	ebay.com
8.		Canon SX740	..	+	3.5/5	..	4/5	4/5	Jul 2018	399	amazon.com
9.		Fujifilm XF10	..	..	4/5	75/100	4/5	4.5/5	Jul 2018	499	ebay.com
10.		Panasonic TZ200	..	+ +	4.5/5	81/100	4.5/5	4.5/5	Feb 2018	799	amazon.com
11.		Pentax K-3	4/5	..	..	83/100	5/5	5/5	Oct 2013	1,299	ebay.com
12.		Pentax K-3 II	4.5/5	..	..	..	5/5	5/5	Apr 2015	1,099	ebay.com
13.		Pentax K-70	4.5/5	..	4/5	79/100	4.5/5	4.5/5	Jun 2016	649	ebay.com
14.		Pentax KP	4/5	..	3/5	82/100	5/5	4.5/5	Jan 2017	1,099	ebay.com
15.		Pentax K-S1	4/5	..	..	..	4.5/5	4/5	Aug 2014	749	ebay.com
16.		Sony RX100 VI	4.5/5	+ +	..	83/100	4/5	4.5/5	Jun 2018	1,199	ebay.com
17.		Sony ZV-1	4/5	+	4/5	85/100	4/5	4.5/5	May 2020	799	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

The review scores listed above should be treated 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 comparisons of ratings among very different cameras or across long time periods have little meaning. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

Check G7X Mark III price at
amazon.com
Check K-S2 offers at
ebay.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. Alternatively, you can follow any of the listed hyperlinks for comparisons that others found interesting.

~

Check G7X Mark III price at
amazon.com
Check K-S2 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.