Canon RP vs Sony A7S III

The Canon EOS RP and the Sony Alpha 7S III are two digital cameras that were revealed to the public, respectively, in February 2019 and July 2020. Both the RP and the A7S III are mirrorless interchangeable lens cameras that are equipped with a full frame sensor. The Canon has a resolution of 26 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 RP		Sony A7S III
Mirrorless system camera		Mirrorless system camera
Canon RF mount lenses		Sony E mount lenses
26 MP – Full Frame sensor		12 MP – Full Frame sensor
4K/30p Video		4K/120p Video
ISO 100-40,000 (50 - 102,400)		ISO 80-102,400 (40 - 409,600)
Electronic viewfinder (2360k dots)		Electronic viewfinder (9440k dots)
3.0" LCD – 1040k dots		3.0" LCD – 1440k dots
Swivel touchscreen		Swivel touchscreen
5 shutter flaps per second		10 shutter flaps per second
Lens stabilization only		In-body stabilization
not weather sealed		Weathersealed body
250 shots per battery charge		600 shots per battery charge
133 x 85 x 70 mm, 485 g		127 x 97 x 81 mm, 699 g

Check RP price at
amazon.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 RP 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 side-by-side display below illustrates the physical size and weight of the Canon RP and the Sony A7S III. 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 III is notably larger (9 percent) than the Canon RP. Moreover, the A7S III is substantially heavier (44 percent) than the RP. It is noteworthy in this context that the A7S III is splash and dust-proof, while the RP 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 RP gets 250 shots out of its Canon LP-E17 battery, while the A7S III can take 600 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 following table provides a synthesis of the main physical specifications of the two cameras and other similar ones. In case you want to display and compare another camera duo, you can use the CAM-parator app to select your camera combination among a large number of options.

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 RP	133 mm	85 mm	70 mm	485 g	250	n	Feb 2019	1,299	amazon.com
2.		Sony A7S III	127 mm	97 mm	81 mm	699 g	600	Y	Jul 2020	3,499	amazon.com
3.		Canon M5	116 mm	89 mm	61 mm	427 g	295	n	Sep 2016	979	ebay.com
4.		Canon R	139 mm	98 mm	84 mm	660 g	370	Y	Sep 2018	2,299	ebay.com
5.		Canon R8	133 mm	86 mm	70 mm	461 g	220	n	Feb 2023	1,499	amazon.com
6.		Canon SL2	122 mm	93 mm	70 mm	453 g	650	n	Jun 2017	549	ebay.com
7.		Canon SL3	122 mm	93 mm	70 mm	449 g	1070	n	Apr 2019	599	amazon.com
8.		Canon T6s	132 mm	101 mm	78 mm	565 g	440	n	Feb 2015	649	ebay.com
9.		Canon T7	129 mm	101 mm	78 mm	475 g	500	n	Feb 2018	449	amazon.com
10.		Sony A7R III	127 mm	96 mm	74 mm	650 g	650	Y	Oct 2017	3,199	ebay.com
11.		Sony A7R IV	129 mm	96 mm	78 mm	665 g	670	Y	Jul 2019	3,499	ebay.com
12.		Sony A7R IVA	129 mm	96 mm	78 mm	665 g	670	Y	Apr 2021	3,499	amazon.com
13.		Sony A7S II	127 mm	96 mm	60 mm	627 g	370	Y	Sep 2015	2,999	ebay.com
14.		Sony A9 II	129 mm	96 mm	76 mm	678 g	690	Y	Oct 2019	4,499	amazon.com
15.		Sony NEX-7	120 mm	67 mm	43 mm	400 g	430	n	Aug 2011	1,349	ebay.com
16.		Sony RX1	113 mm	65 mm	70 mm	482 g	270	n	Sep 2012	2,799	ebay.com
17.		Sony RX1R	113 mm	65 mm	70 mm	482 g	270	n	Jun 2013	2,799	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 manufacturer’s suggested retail prices give an idea on the placement of the camera in the maker’s lineup and the broader market. The RP was launched at a markedly lower price (by 63 percent) than the A7S III, which puts it into a different market segment. 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 sensor inside a digital camera is one of the key determinants 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 are more costly to manufacture and tend to 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 A7S III is 2 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.

With 26MP, the RP offers a higher resolution than the A7S III (12MP), but the RP has smaller individual pixels (pixel pitch of 5.76μm versus 8.40μm for the A7S III). Moreover, the A7S III is a somewhat more recent model (by 1 year and 5 months) than the RP, and its sensor might have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixels.

The resolution advantage of the Canon RP implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the RP for good quality output (200 dots per inch) amounts to 31.2 x 20.8 inches or 79.2 x 52.8 cm, for very good quality (250 dpi) 25 x 16.6 inches or 63.4 x 42.3 cm, and for excellent quality (300 dpi) 20.8 x 13.9 inches or 52.8 x 35.2 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 RP has a native sensitivity range from ISO 100 to ISO 40000, which can be extended to ISO 50-102400. 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 RP 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.

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"). The Overall DXO ratings for the two cameras under consideration are close, suggesting that they provide similar imaging performance. 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.		Canon RP	Full Frame	26.0	6240	4160	4K/30p	24.3	11.9	2977	85
2.		Sony A7S III	Full Frame	12.0	4240	2832	4K/120p	23.7	13.9	2520	86
3.		Canon M5	APS-C	24.0	6000	4000	1080/60p	23.4	12.4	1262	77
4.		Canon R	Full Frame	30.1	6720	4480	4K/30p	24.5	13.5	2742	89
5.		Canon R8	Full Frame	24.0	6000	4000	4k/60p	24.5	14.7	3295	93
6.		Canon SL2	APS-C	24.0	6000	4000	1080/60p	23.6	13.4	1041	79
7.		Canon SL3	APS-C	24.0	6000	4000	4K/25p	23.9	13.4	1791	82
8.		Canon T6s	APS-C	24.0	6000	4000	1080/30p	22.6	12.0	915	70
9.		Canon T7	APS-C	24.0	6000	4000	1080/30p	23.8	13.3	1684	81
10.		Sony A7R III	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
11.		Sony A7R IV	Full Frame	60.2	9504	6336	4K/30p	26.0	14.8	3344	99
12.		Sony A7R IVA	Full Frame	60.2	9504	6336	4K/30p	26.0	14.8	3344	99
13.		Sony A7S II	Full Frame	12.0	4240	2832	4K/30p	23.6	13.3	2993	85
14.		Sony A9 II	Full Frame	24.0	6000	4000	4K/30p	25.0	14.0	3434	93
15.		Sony NEX-7	APS-C	24.0	6000	4000	1080/60i	24.1	13.4	1016	81
16.		Sony RX1	Full Frame	24.0	6000	4000	1080/60p	25.1	14.3	2534	93
17.		Sony RX1R	Full Frame	24.0	6000	4000	1080/60p	25.0	13.6	2537	91
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. The two cameras under consideration both have sensors whose read-out speed is fast enough to capture moving pictures, but the A7S III provides a faster frame rate than the RP. It can shoot movie footage at 4K/120p, while the Canon is limited to 4K/30p.

Feature comparison

Apart from body and sensor, cameras can and do differ across a variety of features. The two cameras under review are similar with respect to both having an electronic viewfinder. However, the one in the A7S III offers a substantially higher resolution than the one in the RP (9440k vs 2360k dots). The adjacent table lists some of the other core features of the Canon RP and Sony A7S III 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 RP	2360	n	3.0 / 1040	swivel	Y	1/4000s	5.0/s	n	n
2.		Sony A7S III	9440	n	3.0 / 1440	swivel	Y	1/8000s	10.0/s	n	Y
3.		Canon M5	2360	n	3.2 / 1620	tilting	Y	1/4000s	9.0/s	Y	n
4.		Canon R	3690	Y	3.2 / 2100	swivel	Y	1/8000s	8.0/s	n	n
5.		Canon R8	2360	n	3.0 / 1620	swivel	Y	1/4000s	6.0/s	n	n
6.		Canon SL2	optical	n	3.0 / 1040	swivel	Y	1/4000s	5.0/s	Y	n
7.		Canon SL3	optical	n	3.0 / 1040	swivel	Y	1/4000s	5.0/s	Y	n
8.		Canon T6s	optical	Y	3.0 / 1040	swivel	Y	1/4000s	5.0/s	Y	n
9.		Canon T7	optical	n	3.0 / 920	fixed	n	1/4000s	3.0/s	Y	n
10.		Sony A7R III	3686	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
11.		Sony A7R IV	5760	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
12.		Sony A7R IVA	5760	n	3.0 / 2340	tilting	Y	1/8000s	10.0/s	n	Y
13.		Sony A7S II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
14.		Sony A9 II	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
15.		Sony NEX-7	2359	n	3.0 / 921	tilting	n	1/4000s	10.0/s	Y	n
16.		Sony RX1	optional	n	3.0 / 1229	fixed	n	1/4000s	5.0/s	Y	n
17.		Sony RX1R	optional	n	3.0 / 1229	fixed	n	1/4000s	5.0/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 RP is in-body image stabilization (IBIS). The A7S III reduces the risk of handshake-induced blur with all attached lenses, while the RP 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 RP 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 RP 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 RP only has one slot. Moreover, both cameras support UHS-II cards (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 Canon EOS RP 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 RP	Y	stereo / mono	Y	Y	micro	2.0	Y	-	Y
2.		Sony A7S III	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
3.		Canon M5	Y	stereo / mono	Y	-	mini	2.0	Y	Y	Y
4.		Canon R	Y	stereo / mono	Y	Y	mini	3.1	Y	-	Y
5.		Canon R8	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
6.		Canon SL2	Y	stereo / mono	Y	-	mini	2.0	Y	Y	Y
7.		Canon SL3	Y	stereo / mono	Y	-	mini	2.0	Y	-	Y
8.		Canon T6s	Y	stereo / mono	Y	-	mini	2.0	Y	Y	-
9.		Canon T7	Y	mono / mono	-	-	mini	2.0	Y	Y	-
10.		Sony A7R III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
11.		Sony A7R IV	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
12.		Sony A7R IVA	Y	stereo / mono	Y	Y	micro	3.2	Y	Y	Y
13.		Sony A7S II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
14.		Sony A9 II	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
15.		Sony NEX-7	Y	stereo / mono	Y	-	mini	2.0	-	-	-
16.		Sony RX1	Y	stereo / mono	Y	-	mini	2.0	-	-	-
17.		Sony RX1R	Y	stereo / mono	Y	-	mini	2.0	-	-	-

Both the RP and the A7S III are recent models that are part of the current product line-up. The A7S III replaced the earlier Sony A7S II, while the RP does not have a direct predecessor. Further information on the features and operation of the RP and A7S III can be found, respectively, in the Canon RP Manual (free pdf) or the online Sony A7S III Manual.

Review summary

So what is the bottom line? Is the Canon RP better than the Sony A7S III or vice versa? The listing below highlights the relative strengths of the two models.

Advantages of the Canon EOS RP:

• More detail: Offers more megapixels (26 vs 12MP) with a 47% higher linear resolution.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• Less heavy: Is lighter (by 214g or 31 percent) and hence easier to carry around.
• More affordable: Was introduced into a lower priced category (63 percent cheaper at launch).
• More heavily discounted: Has been on the market for longer (launched in February 2019).

Arguments in favor of the Sony Alpha 7S III:

• More dynamic range: Captures a broader range of light and dark details (2 EV of extra DR).
• Better video: Provides higher movie framerates (4K/120p versus 4K/30p).
• More detailed viewfinder: Has higher resolution electronic viewfinder (9440k vs 2360k dots).
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.91x vs 0.70x).
• More detailed LCD: Has a higher resolution rear screen (1440k vs 1040k dots).
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
• Faster burst: Shoots at higher frequency (10 vs 5 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 250) out of a single battery charge.
• 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).
• More solid recording: Has a full-sized HDMI port for a sturdy connection to an external recorder.
• Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
• More modern: Was introduced somewhat (1 year and 5 months) more recently.

If the count of relative strengths (bullet points above) is taken as a measure, the A7S III is the clear winner of the contest (15 : 5 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 RP 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 says little about, for example, the shooting experience and imaging performance of the RP and the A7S III in practical situations. 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.		Canon RP	4/5	+	4/5	..	4.5/5	4/5	Feb 2019	1,299	amazon.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 M5	4/5	+	4/5	82/100	4/5	4/5	Sep 2016	979	ebay.com
4.		Canon R	4/5	o	4/5	79/100	4.5/5	4/5	Sep 2018	2,299	ebay.com
5.		Canon R8	4.5/5	+ +	4.5/5	87/100	4/5	4.5/5	Feb 2023	1,499	amazon.com
6.		Canon SL2	4/5	+ +	4/5	78/100	4.5/5	4.5/5	Jun 2017	549	ebay.com
7.		Canon SL3	4/5	o	4.5/5	79/100	4/5	4/5	Apr 2019	599	amazon.com
8.		Canon T6s	5/5	+	..	77/100	4.5/5	4.5/5	Feb 2015	649	ebay.com
9.		Canon T7	..	o	3.5/5	..	3.5/5	3.5/5	Feb 2018	449	amazon.com
10.		Sony A7R III	..	+ +	4/5	90/100	4.5/5	5/5	Oct 2017	3,199	ebay.com
11.		Sony A7R IV	5/5	+	4.5/5	91/100	4.5/5	5/5	Jul 2019	3,499	ebay.com
12.		Sony A7R IVA	5/5	+	4.5/5	91/100	4.5/5	5/5	Apr 2021	3,499	amazon.com
13.		Sony A7S II	5/5	+	..	..	4.5/5	5/5	Sep 2015	2,999	ebay.com
14.		Sony A9 II	..	..	5/5	90/100	5/5	5/5	Oct 2019	4,499	amazon.com
15.		Sony NEX-7	5/5	+ +	..	81/100	4.5/5	5/5	Aug 2011	1,349	ebay.com
16.		Sony RX1	5/5	..	..	79/100	4/5	4.5/5	Sep 2012	2,799	ebay.com
17.		Sony RX1R	5/5	..	..	..	4/5	4.5/5	Jun 2013	2,799	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

Care should be taken when interpreting the review scores above, though. The ratings were established in reference to similarly priced cameras that were available in the market at the time of the review. Thus, a score needs to be put into the context of the launch date and the launch price of the camera, 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.

Check RP price at
amazon.com
Check A7S III price at
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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Check RP price at
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