Sony RX100 III vs Pentax K-70

The Sony Cyber-shot DSC-RX100 III and the Pentax K-70 are two digital cameras that were revealed to the public, respectively, in May 2014 and June 2016. The RX100 III is a fixed lens compact, while the K-70 is a DSLR. The cameras are based on an one-inch (RX100 III) and an APS-C (K-70) sensor. The Sony has a resolution of 20 megapixels, whereas the Pentax provides 24 MP.

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

Headline Specifications

Sony RX100 III		Pentax K-70
Fixed lens compact camera		Digital single lens reflex
24-70mm f/1.8-2.8		Pentax K mount lenses
20 MP – 1" sensor		24 MP – APS-C sensor
1080/60p Video		1080/60i Video
ISO 100-12,800 (80 - 25,600)		ISO 100-102,400
Electronic viewfinder (1440k dots)		Optical viewfinder
3.0" LCD – 1229k dots		3.0" LCD – 921k dots
Tilting screen (no touchscreen)		Swivel screen (not touch-sensitive)
10 shutter flaps per second		6 shutter flaps per second
Lens-based stabilization		In-body stabilization
not weather sealed		Weathersealed body
320 shots per battery charge		410 shots per battery charge
102 x 58 x 41 mm, 290 g		126 x 93 x 74 mm, 688 g

Check RX100 III offers at
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Check K-70 offers at
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Going beyond this snapshot of core features and characteristics, what are the differences between the Sony Cyber-shot DSC-RX100 III and the Pentax K-70? 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 Sony RX100 III and the Pentax K-70 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 size dimensions are rounded to the nearest millimeter.

The K-70 can be obtained in two different colors (black, silver), while the RX100 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 Pentax K-70 is considerably larger (98 percent) than the Sony RX100 III. It is noteworthy in this context that the K-70 is splash and dust-proof, while the RX100 III does not feature any corresponding weather-sealing.

The above size and weight comparisons are to some extent incomplete and possibly misleading, as the RX100 III has a lens built in, whereas the K-70 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 RX100 III gets 320 shots out of its Sony NP-BX1 battery, while the K-70 can take 410 images on a single charge of its Pentax D-LI109 power pack. The power pack in the RX100 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 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 RX100 III	102 mm	58 mm	41 mm	290 g	320	n	May 2014	799	ebay.com
2.		Pentax K-70	126 mm	93 mm	74 mm	688 g	410	Y	Jun 2016	649	ebay.com
3.		Canon G5 X	112 mm	76 mm	44 mm	353 g	210	n	Oct 2015	799	ebay.com
4.		Canon G7 X	103 mm	60 mm	40 mm	304 g	210	n	Sep 2014	699	ebay.com
5.		Panasonic FZ1000	137 mm	99 mm	131 mm	831 g	360	n	Jun 2014	899	ebay.com
6.		Pentax K-3 II	131 mm	100 mm	77 mm	800 g	720	Y	Apr 2015	1,099	ebay.com
7.		Pentax K-3 III	135 mm	104 mm	74 mm	820 g	800	Y	Mar 2021	1,999	amazon.com
8.		Pentax K-50	130 mm	97 mm	71 mm	650 g	410	Y	Jun 2013	599	ebay.com
9.		Pentax KP	132 mm	101 mm	76 mm	703 g	390	Y	Jan 2017	1,099	ebay.com
10.		Pentax K-S2	123 mm	91 mm	73 mm	678 g	410	Y	Feb 2015	749	ebay.com
11.		Sony RX100	102 mm	58 mm	36 mm	240 g	330	n	Jun 2012	649	ebay.com
12.		Sony RX100 II	102 mm	58 mm	38 mm	281 g	350	n	Jun 2013	749	ebay.com
13.		Sony RX100 IV	102 mm	58 mm	41 mm	298 g	280	n	Jun 2015	999	ebay.com
14.		Sony RX100 V	102 mm	58 mm	41 mm	299 g	220	n	Oct 2016	999	ebay.com
15.		Sony RX100 VII	102 mm	58 mm	43 mm	302 g	260	n	Jul 2019	1,199	amazon.com
16.		Sony ZV-1	105 mm	60 mm	44 mm	294 g	260	n	May 2020	799	ebay.com
17.		Sony ZV-1 II	106 mm	60 mm	47 mm	292 g	290	n	May 2023	899	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

Any camera decision will obviously take relative prices into account. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. 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 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 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. 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 associated with larger, more expensive camera bodies and lenses.

Of the two cameras under consideration, the Sony RX100 III features an one-inch sensor and the Pentax K-70 an APS-C sensor. The sensor area in the K-70 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.

With 24MP, the K-70 offers a higher resolution than the RX100 III (20MP), but the K-70 nevertheless has larger individual pixels (pixel pitch of 3.91μm versus 2.41μm for the RX100 III) due to its larger sensor. Moreover, the K-70 is a much more recent model (by 2 years) than the RX100 III, and its sensor will have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixel-units. Coming back to sensor resolution, it should be mentioned that the K-70 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The resolution advantage of the Pentax K-70 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the K-70 for good quality output (200 dots per inch) amounts to 30 x 20 inches or 76.2 x 50.8 cm, for very good quality (250 dpi) 24 x 16 inches or 61 x 40.6 cm, and for excellent quality (300 dpi) 20 x 13.3 inches or 50.8 x 33.9 cm. The corresponding values for the Sony RX100 III are 27.4 x 18.2 inches or 69.5 x 46.3 cm for good quality, 21.9 x 14.6 inches or 55.6 x 37.1 cm for very good quality, and 18.2 x 12.2 inches or 46.3 x 30.9 cm for excellent quality prints.

The K-70 has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

Unlike the RX100 III, the K-70 has the capacity to capture high quality composite images 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 Sony Cyber-shot DSC-RX100 III has a native sensitivity range from ISO 100 to ISO 12800, which can be extended to ISO 80-25600. The corresponding ISO settings for the Pentax K-70 are ISO 100 to ISO 102400 (no boost).

In terms of underlying technology, the RX100 III is build around a BSI-CMOS sensor, while the K-70 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 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 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 RX100 III	1-inch	20.0	5472	3648	1080/60p	22.4	12.3	495	67
2.		Pentax K-70	APS-C	24.0	6000	4000	1080/60i	23.8	13.1	1639	80
3.		Canon G5 X	1-inch	20.0	5472	3648	1080/60p	21.4	12.3	471	62
4.		Canon G7 X	1-inch	20.0	5472	3648	1080/60p	23.0	12.7	556	71
5.		Panasonic FZ1000	1-inch	20.0	5472	3648	4K/30p	22.1	11.7	517	64
6.		Pentax K-3 II	APS-C	24.1	6016	4000	1080/60i	23.6	13.6	1106	80
7.		Pentax K-3 III	APS-C	25.6	6192	4128	4K/30p	24.2	13.7	2083	85
8.		Pentax K-50	APS-C	16.1	4928	3264	1080/30p	23.7	13.0	1120	79
9.		Pentax KP	APS-C	24.1	6016	4000	1080/60i	23.9	13.2	1699	81
10.		Pentax K-S2	APS-C	20.0	5472	3648	1080/30p	23.6	12.9	1514	79
11.		Sony RX100	1-inch	20.0	5472	3648	1080/60p	22.6	12.4	390	66
12.		Sony RX100 II	1-inch	20.0	5472	3648	1080/60p	22.5	12.4	483	67
13.		Sony RX100 IV	1-inch	20.0	5472	3648	4K/30p	22.8	12.6	591	70
14.		Sony RX100 V	1-inch	20.0	5472	3648	4K/30p	22.8	12.4	586	70
15.		Sony RX100 VII	1-inch	20.0	5472	3648	4K/30p	21.8	12.4	418	63
16.		Sony ZV-1	1-inch	20.0	5472	3648	4K/30p	22.2	12.6	669	66
17.		Sony ZV-1 II	1-inch	20.0	5472	3648	4K/30p	22.3	12.9	965	67
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 can also record movies. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, but the RX100 III provides a higher frame rate than the K-70. It can shoot video footage at 1080/60p, while the Pentax is limited to 1080/60i.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. For example, the RX100 III has an electronic viewfinder (1440k dots), while the K-70 has an optical one. Both systems have their advantages, with the electronic viewfinder making it possible to project supplementary shooting information into the framing view, whereas the optical viewfinder offers lag-free viewing and a very clear framing image. The viewfinders of both cameras offer the same field of view (100%), but the viewfinder of the K-70 has a higher magnification than the one of the RX100 III (0.63x vs 0.59x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The table below summarizes some of the other core capabilities of the Sony RX100 III and Pentax K-70 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.		Sony RX100 III	1440	n	3.0 / 1229	tilting	n	1/2000s	10.0/s	Y	Y
2.		Pentax K-70	optical	n	3.0 / 921	swivel	n	1/6000s	6.0/s	Y	Y
3.		Canon G5 X	2360	n	3.0 / 1040	swivel	Y	1/2000s	5.9/s	Y	Y
4.		Canon G7 X	none	n	3.0 / 1040	tilting	Y	1/2000s	6.5/s	Y	Y
5.		Panasonic FZ1000	2359	n	3.0 / 921	swivel	n	1/4000s	12.0/s	Y	Y
6.		Pentax K-3 II	optical	Y	3.2 / 1037	fixed	n	1/8000s	8.3/s	n	Y
7.		Pentax K-3 III	optical	Y	3.2 / 1620	fixed	Y	1/8000s	12.0/s	n	Y
8.		Pentax K-50	optical	n	3.0 / 921	fixed	n	1/6000s	6.0/s	Y	Y
9.		Pentax KP	optical	n	3.0 / 921	tilting	n	1/6000s	7.0/s	Y	Y
10.		Pentax K-S2	optical	n	3.0 / 921	swivel	n	1/6000s	5.4/s	Y	Y
11.		Sony RX100	none	n	3.0 / 1229	fixed	n	1/2000s	10.0/s	Y	Y
12.		Sony RX100 II	optional	n	3.0 / 1229	tilting	n	1/2000s	10.0/s	Y	Y
13.		Sony RX100 IV	2359	n	3.0 / 1228	tilting	n	1/2000s	16.0/s	Y	Y
14.		Sony RX100 V	2359	n	3.0 / 1229	tilting	n	1/2000s	24.0/s	Y	Y
15.		Sony RX100 VII	2359	n	3.0 / 921	tilting	Y	1/2000s	90.0/s	Y	Y
16.		Sony ZV-1	none	n	3.0 / 922	swivel	Y	1/2000s	24.0/s	n	n
17.		Sony ZV-1 II	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.

The Pentax K-70 has 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 RX100 III writes its imaging data to SDXC or Memory Stick PRO Duo cards, while the K-70 uses 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 Sony Cyber-shot DSC-RX100 III and Pentax K-70 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 RX100 III	-	stereo / mono	-	-	micro	2.0	Y	Y	-
2.		Pentax K-70	Y	stereo / mono	Y	-	mini	2.0	Y	-	-
3.		Canon G5 X	Y	stereo / mono	-	-	mini	2.0	Y	Y	-
4.		Canon G7 X	-	stereo / mono	-	-	micro	2.0	Y	Y	-
5.		Panasonic FZ1000	Y	stereo / mono	Y	-	micro	2.0	Y	Y	-
6.		Pentax K-3 II	Y	mono / mono	Y	Y	mini	3.0	-	-	-
7.		Pentax K-3 III	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
8.		Pentax K-50	Y	mono / mono	-	-	micro	2.0	-	-	-
9.		Pentax KP	Y	stereo / mono	Y	-	-	2.0	Y	-	-
10.		Pentax K-S2	Y	mono / mono	Y	-	micro	2.0	Y	Y	-
11.		Sony RX100	-	stereo / mono	-	-	micro	2.0	-	-	-
12.		Sony RX100 II	Y	stereo / mono	-	-	micro	2.0	Y	Y	-
13.		Sony RX100 IV	-	stereo / mono	-	-	micro	2.0	Y	Y	-
14.		Sony RX100 V	-	stereo / mono	-	-	micro	2.0	Y	Y	-
15.		Sony RX100 VII	-	stereo / mono	Y	-	micro	2.0	Y	Y	Y
16.		Sony ZV-1	Y	stereo / mono	Y	-	micro	2.0	Y	-	Y
17.		Sony ZV-1 II	Y	stereo / mono	Y	-	micro	2.0	Y	-	Y

It is notable that the K-70 has a microphone port, which can help to improve the quality of audio recordings by attaching an external microphone. The RX100 III does not feature such a mic input.

Both the RX100 III and the K-70 have been discontinued, but can regularly be found used on ebay. The RX100 III was replaced by the Sony RX100 IV, while the K-70 does not have a direct successor. Further information on the features and operation of the RX100 III and K-70 can be found, respectively, in the Sony RX100 III Manual (free pdf) or the online Pentax K-70 Manual.

Review summary

So how do things add up? Is the Sony RX100 III better than the Pentax K-70 or vice versa? Below is a summary of the relative strengths of each of the two contestants.

Reasons to prefer the Sony Cyber-shot DSC-RX100 III:

• Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
• Better video: Provides higher movie framerates (1080/60p versus 1080/60i).
• More framing info: Has an electronic viewfinder that displays shooting data.
• More detailed LCD: Has a higher resolution rear screen (1229k vs 921k dots).
• Faster burst: Shoots at higher frequency (10 vs 6 flaps/sec) to capture the decisive moment.
• Ready to shoot: Comes with a built-in lens, while the K-70 requires a separate lens.
• More compact: Is smaller (102x58mm vs 126x93mm) and thus needs less room in the bag.
• Less heavy: Is lighter even though it comes with a built-in lens (unlike the K-70).
• Easier travel charging: Can be conveniently charged via its USB port.
• Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
• More heavily discounted: Has been available for much longer (launched in May 2014).

Advantages of the Pentax K-70:

• More detail: Has more megapixels (24 vs 20MP), which boosts linear resolution by 10%.
• 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 image quality: Is equipped with a larger and more technologically advanced sensor.
• Richer colors: The sensor size advantage translates into images with better, more accurate colors.
• More dynamic range: Larger sensor captures a wider spectrum of light and dark details.
• Better low-light sensitivity: Larger sensor produces good images even in poorly lit environments.
• Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
• Better sound: Can connect to an external microphone for higher quality sound recording.
• Brighter framing: Features an optical viewfinder for clear, lag-free composition.
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.63x vs 0.59x).
• 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.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• More flexible: Makes it possible to change lenses and thus to use specialty optics.
• Longer lasting: Gets more shots (410 versus 320) 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.
• More modern: Reflects 2 years of technical progress since the RX100 III launch.

If the count of individual advantages (bullet points above) is taken as a guide, the K-70 is the clear winner of the contest (19 : 11 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 sports photographer will view the differences between cameras in a way that diverges from the perspective of a street photog, and a person interested in family portraits has distinct needs from a landscape 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 RX100 III and the Pentax K-70 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 incomplete and does no justice, for example, to the way the RX100 III or the K-70 perform in practice. User reviews, such as those found at amazon, can sometimes inform about these issues, but such feedback is often incomplete, inconsistent, and biased.

Expert reviews

This is why expert reviews 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.		Sony RX100 III	5/5	+ +	..	82/100	4.5/5	5/5	May 2014	799	ebay.com
2.		Pentax K-70	4.5/5	..	4/5	79/100	4.5/5	4.5/5	Jun 2016	649	ebay.com
3.		Canon G5 X	5/5	+ +	..	78/100	4.5/5	4.5/5	Oct 2015	799	ebay.com
4.		Canon G7 X	4/5	+ +	..	77/100	4.5/5	4.5/5	Sep 2014	699	ebay.com
5.		Panasonic FZ1000	4/5	+ +	..	82/100	4.5/5	4.5/5	Jun 2014	899	ebay.com
6.		Pentax K-3 II	4.5/5	..	..	..	5/5	5/5	Apr 2015	1,099	ebay.com
7.		Pentax K-3 III	4/5	..	3/5	..	4.5/5	..	Mar 2021	1,999	amazon.com
8.		Pentax K-50	5/5	..	..	..	5/5	4.5/5	Jun 2013	599	ebay.com
9.		Pentax KP	4/5	..	3/5	82/100	5/5	4.5/5	Jan 2017	1,099	ebay.com
10.		Pentax K-S2	4.5/5	..	..	..	5/5	4.5/5	Feb 2015	749	ebay.com
11.		Sony RX100	5/5	+ +	..	78/100	4/5	5/5	Jun 2012	649	ebay.com
12.		Sony RX100 II	5/5	+ +	..	79/100	4.5/5	4.5/5	Jun 2013	749	ebay.com
13.		Sony RX100 IV	4.5/5	+ +	..	85/100	4/5	4.5/5	Jun 2015	999	ebay.com
14.		Sony RX100 V	4.5/5	+ +	..	83/100	4/5	4.5/5	Oct 2016	999	ebay.com
15.		Sony RX100 VII	4.5/5	..	4/5	..	4/5	5/5	Jul 2019	1,199	amazon.com
16.		Sony ZV-1	4/5	+	4/5	85/100	4/5	4.5/5	May 2020	799	ebay.com
17.		Sony ZV-1 II	4.5/5	..	3.5/5	83/100	3.5/5	4.5/5	May 2023	899	amazon.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 rating-comparisons among cameras that span long time periods or concern very differently equipped models make little sense. Also, please note that some of the review sites have changed their methodology and reporting over time.

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Other camera comparisons

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