Leica SL vs Sony A9 III

The Leica SL (Typ 601) and the Sony Alpha A9 III are two digital cameras that were revealed to the public, respectively, in October 2015 and November 2023. Both the Leica SL and the A9 III are mirrorless interchangeable lens cameras that are equipped with a full frame sensor. Both cameras offer a resolution of 24 megapixels.

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

Headline Specifications

Leica SL		Sony A9 III
Mirrorless system camera		Mirrorless system camera
Leica L mount lenses		Sony E mount lenses
24 MP – Full Frame sensor		24 MP – Full Frame sensor
4K/30p Video		4K/120p Video
ISO 50-50,000		ISO 250-25,600 (125 - 51,200)
Electronic viewfinder (4400k dots)		Electronic viewfinder (9440k dots)
3.0" LCD – 1040k dots		3.2" LCD – 2100k dots
Fixed touchscreen		Fully flexible touchscreen
11 shutter flaps per second		120 shutter flaps per second
Lens stabilization only		In-body stabilization
Weathersealed body		Weathersealed body
400 shots per battery charge		530 shots per battery charge
147 x 104 x 39 mm, 847 g		136 x 97 x 83 mm, 702 g

Check Leica SL offers at
ebay.com
Check A9 III price at
amazon.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Leica SL (Typ 601) 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

The physical size and weight of the Leica SL and the Sony A9 III are illustrated in the side-by-side display below. The two cameras are presented according to their relative size. Three consecutive perspectives from the front, the top, and the back are available. All width, height and depth 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 smaller (14 percent) than the Leica SL. Moreover, the A9 III is markedly lighter (17 percent) than the Leica SL. 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 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 Leica SL gets 400 shots out of its Leica BP-SCL4 battery, while the A9 III can take 530 images on a single charge of its Sony NP-FZ100 power pack. The power pack in the A9 III 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	Street Price
1.		Leica SL	147 mm	104 mm	39 mm	847 g	400	Y	Oct 2015	US$ 7 449	ebay.com
2.		Sony A9 III	136 mm	97 mm	83 mm	702 g	530	Y	Nov 2023	US$ 5 999	amazon.com
3.		Canon 80D	139 mm	105 mm	79 mm	730 g	960	Y	Feb 2016	US$ 1 199	ebay.com
4.		Hasselblad X1D	150 mm	98 mm	71 mm	725 g	..	Y	Jun 2016	US$ 8 995	ebay.com
5.		Leica M Typ 240	139 mm	80 mm	42 mm	680 g	500	Y	Sep 2012	US$ 6 949	ebay.com
6.		Leica M10	139 mm	80 mm	39 mm	660 g	210	Y	Jan 2017	US$ 6 599	ebay.com
7.		Leica SL2	146 mm	107 mm	42 mm	953 g	370	Y	Nov 2019	US$ 5 999	amazon.com
8.		Leica SL2-S	146 mm	107 mm	83 mm	931 g	510	Y	Dec 2020	US$ 4 899	amazon.com
9.		Nikon D5	160 mm	159 mm	92 mm	1415 g	3780	Y	Jan 2016	US$ 6 499	ebay.com
10.		Nikon D500	147 mm	115 mm	81 mm	860 g	1240	Y	Jan 2016	US$ 1 999	ebay.com
11.		Nikon D750	141 mm	113 mm	78 mm	750 g	1230	Y	Sep 2014	US$ 2 299	ebay.com
12.		Nikon D7200	136 mm	107 mm	76 mm	765 g	1110	Y	Mar 2015	US$ 1 199	ebay.com
13.		Sony A1 II	136 mm	97 mm	83 mm	743 g	520	Y	Nov 2024	US$ 6 499	amazon.com
14.		Sony A7 II	127 mm	96 mm	60 mm	599 g	350	Y	Nov 2014	US$ 1 999	ebay.com
15.		Sony A7 III	127 mm	96 mm	74 mm	650 g	610	Y	Feb 2018	US$ 1 999	amazon.com
16.		Sony A9	127 mm	96 mm	63 mm	673 g	650	Y	Apr 2017	US$ 4 499	ebay.com
17.		Sony A9 II	129 mm	96 mm	76 mm	678 g	690	Y	Oct 2019	US$ 4 499	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 naturally be influenced heavily by the price. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The A9 III was launched at a somewhat lower price (by 19 percent) than the Leica SL, which makes it more attractive for photographers on a tight budget. 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. Then, after the new model is out, very good deals can frequently be found on the pre-owned market.

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. 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.

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.

Even though the Leica SL has a slightly larger sensor, both cameras offer the same resolution of 24 megapixels. This implies that the Leica SL has a lower pixel density and larger individual pixels (with a pixel pitch of 6.00μm versus 5.94μm for the A9 III), which gives it a potential advantage in terms of light gathering capacity. It should, however, be noted that the A9 III is much more recent (by 8 years) than the Leica SL, 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 Leica SL has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The A9 III has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

The Leica SL (Typ 601) has a native sensitivity range from ISO 50 to ISO 50000. 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 Leica SL 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.

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 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.		Leica SL	Full Frame	24.0	6000	4000	4K/30p	25.0	13.4	1821	88
2.		Sony A9 III	Full Frame	24.0	6000	4000	4K/120p	25.4	14.7	3243	96
3.		Canon 80D	APS-C	24.0	6000	4000	1080/60p	23.6	13.2	1135	79
4.		Hasselblad X1D	Medium Format	51.3	8272	6200	1080/25p	26.2	14.8	4489	102
5.		Leica M Typ 240	Full Frame	23.7	5952	3976	1080/25p	24.0	13.3	1860	84
6.		Leica M10	Full Frame	23.8	5952	3992	none	24.4	13.2	2133	86
7.		Leica SL2	Full Frame	46.7	8368	5584	4K/60p	25.3	14.3	2866	95
8.		Leica SL2-S	Full Frame	24.0	6000	4000	4K/60p	25.2	14.1	3504	95
9.		Nikon D5	Full Frame	20.7	5588	3712	4K/30p	25.1	12.3	2343	88
10.		Nikon D500	APS-C	20.7	5568	3712	4K/30p	24.0	14.0	1324	83
11.		Nikon D750	Full Frame	24.2	6016	4016	1080/60p	24.8	14.5	2956	93
12.		Nikon D7200	APS-C	24.0	6000	4000	1080/60p	24.5	14.6	1333	87
13.		Sony A1 II	Full Frame	49.8	8640	5760	8k/30p	25.4	14.8	3363	97
14.		Sony A7 II	Full Frame	24.0	6000	4000	1080/60p	24.9	13.6	2449	90
15.		Sony A7 III	Full Frame	24.0	6000	4000	4K/30p	25.0	14.7	3730	96
16.		Sony A9	Full Frame	24.0	6000	4000	4K/30p	24.9	13.3	3517	92
17.		Sony A9 II	Full Frame	24.0	6000	4000	4K/30p	25.0	14.0	3434	93
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, but the A9 III provides a faster frame rate than the Leica SL. It can shoot movie footage at 4K/120p, while the Leica 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 Leica SL (9440k vs 4400k dots). The following table reports on some other key feature differences and similarities of the Leica SL, the Sony A9 III, and comparable 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.		Leica SL	4400	Y	3.0 / 1040	fixed	Y	1/8000s	11.0/s	n	n
2.		Sony A9 III	9440	n	3.2 / 2100	full-flex	Y	1/80000s	120.0/s	n	Y
3.		Canon 80D	optical	Y	3.0 / 1040	swivel	Y	1/8000s	7.0/s	Y	n
4.		Hasselblad X1D	2360	n	3.0 / 920	fixed	Y	1/2000s	2.3/s	n	n
5.		Leica M Typ 240	optical	n	3.0 / 920	fixed	n	1/4000s	3.0/s	n	n
6.		Leica M10	optical	n	3.0 / 1037	fixed	n	1/4000s	5.0/s	n	n
7.		Leica SL2	5760	Y	3.2 / 2100	fixed	Y	1/8000s	10.0/s	n	Y
8.		Leica SL2-S	5760	Y	3.2 / 2100	fixed	Y	1/8000s	20.0/s	n	Y
9.		Nikon D5	optical	Y	3.2 / 2359	fixed	Y	1/8000s	14.0/s	n	n
10.		Nikon D500	optical	Y	3.2 / 2359	tilting	Y	1/8000s	10.0/s	n	n
11.		Nikon D750	optical	Y	3.2 / 1229	tilting	n	1/4000s	6.0/s	Y	n
12.		Nikon D7200	optical	Y	3.2 / 1229	fixed	n	1/8000s	6.0/s	Y	n
13.		Sony A1 II	9437	n	3.2 / 2100	full-flex	Y	1/8000s	30.0/s	n	Y
14.		Sony A7 II	2400	n	3.0 / 1230	tilting	n	1/8000s	5.0/s	n	Y
15.		Sony A7 III	2359	n	3.0 / 922	tilting	Y	1/8000s	10.0/s	n	Y
16.		Sony A9	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
17.		Sony A9 II	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One feature that is present on the Leica SL, but is missing on the A9 III is a top-level LCD. While being, of course, smaller than the rear screen, the control panel conveys some of the essential shooting information and can be convenient for quick and easy settings verification.

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, both cameras under consideration feature an 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 Leica SL 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 Leica SL writes its imaging data to SDXC cards, while the A9 III uses CFexpress (type A) or SDXC cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. Both cameras support UHS-II cards, which provide for Ultra High Speed data transfer of up to 312 MB/s (the second slot of the Leica SL supports only UHS-I, though).

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 Leica SL (Typ 601) 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.		Leica SL	Y	stereo / mono	Y	Y	full	3.0	Y	-	-
2.		Sony A9 III	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
3.		Canon 80D	Y	stereo / mono	Y	Y	mini	2.0	Y	Y	-
4.		Hasselblad X1D	Y	stereo / mono	Y	Y	mini	3.0	Y	-	-
5.		Leica M Typ 240	Y	stereo / mono	-	-	-	2.0	-	-	-
6.		Leica M10	Y	- / -	-	-	-	-	Y	-	-
7.		Leica SL2	Y	stereo / mono	Y	Y	full	3.1	Y	-	Y
8.		Leica SL2-S	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
9.		Nikon D5	Y	stereo / mono	Y	Y	mini	3.0	-	-	-
10.		Nikon D500	Y	stereo / mono	Y	Y	mini	3.0	Y	Y	Y
11.		Nikon D750	Y	stereo / mono	Y	Y	mini	2.0	Y	-	-
12.		Nikon D7200	Y	stereo / mono	Y	Y	mini	2.0	Y	Y	-
13.		Sony A1 II	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
14.		Sony A7 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
15.		Sony A7 III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
16.		Sony A9	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	Y
17.		Sony A9 II	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y

Both cameras feature a PC Sync terminal to control professional strobe lights, which will be appreciated by studio photographers.

Travel and landscape photographers will find it useful that the Leica SL has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.

The A9 III is a recent model that features in the current product line-up of Sony. In contrast, the Leica SL has been discontinued (but can be found pre-owned on ebay). As a replacement in the same line of cameras, the Leica SL was succeeded by the Leica SL2. Further information on the features and operation of the Leica SL and A9 III can be found, respectively, in the Leica SL Manual (free pdf) or the online Sony A9 III Manual.

Review summary

So how do things add up? Which of the two cameras – the Leica SL or the Sony A9 III – has the upper hand? Is one clearly better than the other? A synthesis of the relative strong points of each of the models is listed below.

Arguments in favor of the Leica SL (Typ 601):

• Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
• Easier setting verification: Features an LCD display on top to control shooting parameters.
• Easier geotagging: Features an internal GPS sensor to log localization data.
• More prestigious: Has the Leica luxury appeal, which ensures a high resale price.
• More heavily discounted: Has been available for much longer (launched in October 2015).

Reasons to prefer the Sony Alpha A9 III:

• Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
• Better video: Provides higher movie framerates (4K/120p versus 4K/30p).
• Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
• More detailed viewfinder: Has higher resolution electronic viewfinder (9440k vs 4400k dots).
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.9x vs 0.80x).
• 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).
• More flexible LCD: Has a full-flex screen for odd-angle shots in portrait or landscape orientation.
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Faster shutter: Has higher mechanical shutter speed (1/80000s vs 1/8000s) to freeze action.
• Faster burst: Shoots at higher frequency (120 vs 11 flaps/sec) to capture the decisive moment.
• More compact: Is smaller (136x97mm vs 147x104mm) and will fit more readily into a bag.
• Less heavy: Has a lower weight (by 145g or 17 percent) and is thus easier to take along.
• Longer lasting: Gets more shots (530 versus 400) out of a single battery charge.
• Easier travel charging: Can be conveniently charged via its USB port.
• Sharper images: Has stabilization technology built-in to reduce the impact of hand-shake.
• Easier wireless transfer: Supports Bluetooth for image sharing without cables.
• More affordable: Was released into a lower priced segment (19 percent cheaper at launch).
• More modern: Reflects 8 years of technical progress since the Leica SL launch.

If the count of individual advantages (bullet points above) is taken as a guide, the A9 III is the clear winner of the contest (19 : 5 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 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 Leica SL 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 remains partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the Leica SL or the A9 III. 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 where reviews by experts come in. 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	Street Price
1.		Leica SL	4/5	..	4/5	84/100	4.5/5	4/5	Oct 2015	US$ 7 449	ebay.com
2.		Sony A9 III	4.5/5	..	..	91/100	..	..	Nov 2023	US$ 5 999	amazon.com
3.		Canon 80D	4/5	+ +	4.5/5	84/100	4.5/5	4.5/5	Feb 2016	US$ 1 199	ebay.com
4.		Hasselblad X1D	..	o	..	81/100	..	4/5	Jun 2016	US$ 8 995	ebay.com
5.		Leica M Typ 240	4/5	..	..	..	4/5	..	Sep 2012	US$ 6 949	ebay.com
6.		Leica M10	4.5/5	..	..	..	4/5	4.5/5	Jan 2017	US$ 6 599	ebay.com
7.		Leica SL2	4/5	..	4.5/5	..	4.5/5	4/5	Nov 2019	US$ 5 999	amazon.com
8.		Leica SL2-S	4/5	..	4/5	..	4.5/5	4.5/5	Dec 2020	US$ 4 899	amazon.com
9.		Nikon D5	..	..	4/5	89/100	4.5/5	5/5	Jan 2016	US$ 6 499	ebay.com
10.		Nikon D500	5/5	+ +	4.7/5	91/100	4.5/5	5/5	Jan 2016	US$ 1 999	ebay.com
11.		Nikon D750	5/5	+ +	4/5	90/100	4.5/5	4.5/5	Sep 2014	US$ 2 299	ebay.com
12.		Nikon D7200	4/5	+ +	..	84/100	4.5/5	4.5/5	Mar 2015	US$ 1 199	ebay.com
13.		Sony A1 II	..	..	..	..	..	..	Nov 2024	US$ 6 499	amazon.com
14.		Sony A7 II	5/5	+	4/5	82/100	4.5/5	5/5	Nov 2014	US$ 1 999	ebay.com
15.		Sony A7 III	..	+ +	4.5/5	89/100	5/5	5/5	Feb 2018	US$ 1 999	amazon.com
16.		Sony A9	5/5	+ +	4.8/5	89/100	5/5	5/5	Apr 2017	US$ 4 499	ebay.com
17.		Sony A9 II	..	..	5/5	90/100	5/5	5/5	Oct 2019	US$ 4 499	amazon.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.

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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 your choice using the following search menu. As an alternative, you can also directly jump to any one of the listed comparisons that were previously generated by the CAM-parator tool.

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