Canon RP vs Sony A9 III

The Canon EOS RP and the Sony Alpha A9 III are two digital cameras that were announced, respectively, in February 2019 and November 2023. Both the RP and the A9 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 24 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 A9 III
Mirrorless system camera		Mirrorless system camera
Canon RF mount lenses		Sony E mount lenses
26 MP – Full Frame sensor		24 MP – Full Frame sensor
4K/30p Video		4K/120p Video
ISO 100-40,000 (50 - 102,400)		ISO 250-25,600 (125 - 51,200)
Electronic viewfinder (2360k dots)		Electronic viewfinder (9440k dots)
3.0" LCD – 1040k dots		3.2" LCD – 2100k dots
Swivel touchscreen		Fully flexible touchscreen
5 shutter flaps per second		120 shutter flaps per second
Lens stabilization only		In-body stabilization
not weather sealed		Weathersealed body
250 shots per battery charge		530 shots per battery charge
133 x 85 x 70 mm, 485 g		136 x 97 x 83 mm, 702 g

Check RP price at
amazon.com
Check A9 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 A9 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

An illustration of the physical size and weight of the Canon RP and the Sony A9 III is provided 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.

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony A9 III is notably larger (17 percent) than the Canon RP. Moreover, the A9 III is substantially heavier (45 percent) than the RP. It is noteworthy in this context that the A9 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 A9 III can take 530 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 adjacent table lists the principal physical characteristics of the two cameras alongside a wider set of alternatives. 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	Street Price
1.		Canon RP	133 mm	85 mm	70 mm	485 g	250	n	Feb 2019	US$ 1 299	amazon.com
2.		Sony A9 III	136 mm	97 mm	83 mm	702 g	530	Y	Nov 2023	US$ 5 999	amazon.com
3.		Canon M5	116 mm	89 mm	61 mm	427 g	295	n	Sep 2016	US$ 979	ebay.com
4.		Canon R	139 mm	98 mm	84 mm	660 g	370	Y	Sep 2018	US$ 2 299	ebay.com
5.		Canon R8	133 mm	86 mm	70 mm	461 g	220	n	Feb 2023	US$ 1 499	amazon.com
6.		Canon SL2	122 mm	93 mm	70 mm	453 g	650	n	Jun 2017	US$ 549	ebay.com
7.		Canon SL3	122 mm	93 mm	70 mm	449 g	1070	n	Apr 2019	US$ 599	amazon.com
8.		Canon T6s	132 mm	101 mm	78 mm	565 g	440	n	Feb 2015	US$ 649	ebay.com
9.		Canon T7	129 mm	101 mm	78 mm	475 g	500	n	Feb 2018	US$ 449	amazon.com
10.		Sony A1	129 mm	97 mm	81 mm	737 g	530	Y	Jan 2021	US$ 6 499	amazon.com
11.		Sony A7 II	127 mm	96 mm	60 mm	599 g	350	Y	Nov 2014	US$ 1 999	ebay.com
12.		Sony A7 III	127 mm	96 mm	74 mm	650 g	610	Y	Feb 2018	US$ 1 999	amazon.com
13.		Sony A9	127 mm	96 mm	63 mm	673 g	650	Y	Apr 2017	US$ 4 499	ebay.com
14.		Sony A9 II	129 mm	96 mm	76 mm	678 g	690	Y	Oct 2019	US$ 4 499	amazon.com
15.		Sony NEX-7	120 mm	67 mm	43 mm	400 g	430	n	Aug 2011	US$ 1 349	ebay.com
16.		Sony RX1	113 mm	65 mm	70 mm	482 g	270	n	Sep 2012	US$ 2 799	ebay.com
17.		Sony RX1R	113 mm	65 mm	70 mm	482 g	270	n	Jun 2013	US$ 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 listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The RP was launched at a markedly lower price (by 78 percent) than the A9 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.

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. 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 more expensive and 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 A9 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 slightly higher resolution than the A9 III (24MP), but the RP has smaller individual pixels (pixel pitch of 5.76μm versus 5.94μm for the A9 III). Moreover, the A9 III is a much more recent model (by 4 years and 8 months) than the RP, and its sensor will have benefitted from technological advances during this time that enhance the light gathering capacity of its pixels.

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 A9 III are ISO 250 to ISO 25600, with the possibility to increase the ISO range to 125-51200.

In terms of underlying technology, the RP is build around a CMOS sensor, while the A9 III uses a Stacked 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 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 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 A9 III	Full Frame	24.0	6000	4000	4K/120p	25.4	14.7	3243	96
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 A1	Full Frame	49.8	8640	5760	8k/30p	25.9	14.5	3163	98
11.		Sony A7 II	Full Frame	24.0	6000	4000	1080/60p	24.9	13.6	2449	90
12.		Sony A7 III	Full Frame	24.0	6000	4000	4K/30p	25.0	14.7	3730	96
13.		Sony A9	Full Frame	24.0	6000	4000	4K/30p	24.9	13.3	3517	92
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. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, but the A9 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

Beyond body and sensor, cameras can and do differ across a range of features. The two cameras under review are similar with respect to both having an electronic viewfinder. However, the one in the A9 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 A9 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 A9 III	9440	n	3.2 / 2100	full-flex	Y	1/80000s	120.0/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 A1	9437	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
11.		Sony A7 II	2400	n	3.0 / 1230	tilting	n	1/8000s	5.0/s	n	Y
12.		Sony A7 III	2359	n	3.0 / 922	tilting	Y	1/8000s	10.0/s	n	Y
13.		Sony A9	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/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 A9 III and the RP is in-body image stabilization (IBIS). The A9 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 A9 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 and the Sony A9 III 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.

The RP writes its imaging data to SDXC cards, while the A9 III uses CFexpress (type A) or SDXC cards. The A9 III features dual card slots, which can be very useful in case a memory card fails. In contrast, the RP only has one slot. Both cameras support UHS-II cards, which provide for 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 A9 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 A9 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 A1	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
11.		Sony A7 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
12.		Sony A7 III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
13.		Sony A9	Y	stereo / mono	Y	Y	micro	2.0	Y	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	-	-	-

Studio photographers will appreciate that the Sony A9 III (unlike the RP) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.

Both the RP and the A9 III are recent models that are part of the current product line-up. The A9 III replaced the earlier Sony A9 II, while the RP does not have a direct predecessor. Further information on the features and operation of the RP and A9 III can be found, respectively, in the Canon RP Manual (free pdf) or the online Sony A9 III Manual.

Review summary

So how do things add up? Is there a clear favorite between the Canon RP and the Sony A9 III? Which camera is better? Below is a summary of the relative strengths of each of the two contestants.

Advantages of the Canon EOS RP:

• More compact: Is smaller (133x85mm vs 136x97mm) and thus needs less room in the bag.
• Less heavy: Is lighter (by 217g or 31 percent) and hence easier to carry around.
• More affordable: Was introduced into a lower priced category (78 percent cheaper at launch).
• More heavily discounted: Has been available for much longer (launched in February 2019).

Arguments in favor of the Sony Alpha A9 III:

• 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 (0.9x vs 0.70x).
• 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 (2100k vs 1040k dots).
• Faster shutter: Has higher mechanical shutter speed (1/80000s vs 1/4000s) to freeze action.
• Faster burst: Shoots at higher frequency (120 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 (530 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.
• Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
• Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
• More modern: Reflects 4 years and 8 months of technical progress since the RP launch.

If the number of relative strengths (bullet points above) is taken as a guide, the A9 III is the clear winner of the contest (16 : 4 points). However, the relevance of individual strengths will vary across photographers, so that you might want to apply your own weighing scheme to the summary points when reflecting and deciding on a new camera. A professional wildlife photographer will view the differences between cameras in a way that diverges from the perspective of a family photog, and a person interested in architecture has distinct needs from a sports 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 A9 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 specs-based evaluation of cameras can be instructive in revealing their potential as photographic tools, it says little about, for example, the shooting experience and imaging performance of the RP and the A9 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 hands-on reviews by experts are important. The following table reports the overall ratings of the cameras as published by some of the major 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	Street Price
1.		Canon RP	4/5	+	4/5	..	4.5/5	4/5	Feb 2019	US$ 1 299	amazon.com
2.		Sony A9 III	4.5/5	..	..	..	..	..	Nov 2023	US$ 5 999	amazon.com
3.		Canon M5	4/5	+	4/5	82/100	4/5	4/5	Sep 2016	US$ 979	ebay.com
4.		Canon R	4/5	o	4/5	79/100	4.5/5	4/5	Sep 2018	US$ 2 299	ebay.com
5.		Canon R8	4.5/5	+ +	4.5/5	87/100	4/5	4.5/5	Feb 2023	US$ 1 499	amazon.com
6.		Canon SL2	4/5	+ +	4/5	78/100	4.5/5	4.5/5	Jun 2017	US$ 549	ebay.com
7.		Canon SL3	4/5	o	4.5/5	79/100	4/5	4/5	Apr 2019	US$ 599	amazon.com
8.		Canon T6s	5/5	+	..	77/100	4.5/5	4.5/5	Feb 2015	US$ 649	ebay.com
9.		Canon T7	..	o	3.5/5	..	3.5/5	3.5/5	Feb 2018	US$ 449	amazon.com
10.		Sony A1	5/5	o	4.5/5	93/100	4.5/5	5/5	Jan 2021	US$ 6 499	amazon.com
11.		Sony A7 II	5/5	+	4/5	82/100	4.5/5	5/5	Nov 2014	US$ 1 999	ebay.com
12.		Sony A7 III	..	+ +	4.5/5	89/100	5/5	5/5	Feb 2018	US$ 1 999	amazon.com
13.		Sony A9	5/5	+ +	4.8/5	89/100	5/5	5/5	Apr 2017	US$ 4 499	ebay.com
14.		Sony A9 II	..	..	5/5	90/100	5/5	5/5	Oct 2019	US$ 4 499	amazon.com
15.		Sony NEX-7	5/5	+ +	..	81/100	4.5/5	5/5	Aug 2011	US$ 1 349	ebay.com
16.		Sony RX1	5/5	..	..	79/100	4/5	4.5/5	Sep 2012	US$ 2 799	ebay.com
17.		Sony RX1R	5/5	..	..	..	4/5	4.5/5	Jun 2013	US$ 2 799	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. 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, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

Check RP price at
amazon.com
Check A9 III price at
amazon.com

Other camera comparisons

Did this review help to inform your camera decision process? In case you are interested in seeing how other cameras pair up, just make a corresponding selection in the search boxes below. Alternatively, you can follow any of the listed hyperlinks for comparisons that others found interesting.

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Check RP price at
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Check A9 III price at
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