Leica SL vs Sony A7R III

The Leica SL (Typ 601) and the Sony Alpha A7R III are two enthusiast cameras that were officially introduced, respectively, in October 2015 and October 2017. Both the SL and the A7R III are mirrorless interchangeable lens cameras that are equipped with a full frame sensor. The Leica has a resolution of 24 megapixels, whereas the Sony provides 42.2 MP.

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

Headline Specifications

Leica SL		Sony A7R III
Mirrorless system camera		Mirrorless system camera
Leica L mount lenses		Sony E mount lenses
24 MP, Full Frame Sensor		42.2 MP, Full Frame Sensor
4K/30p Video		4K/30p Video
ISO 50-50,000		ISO 100-32,000 (50 - 102,400)
Electronic viewfinder (4400k dots)		Electronic viewfinder (3686k dots)
3.0 LCD, 1040k dots		3.0 LCD, 1440k dots
Fixed touchscreen		Tilting touchscreen
11 shutter flaps per second		10 shutter flaps per second
Lens stabilization only		In-body stabilization
Weathersealed body		Weathersealed body
400 shots per battery charge		650 shots per battery charge
147 x 104 x 39 mm, 847 g		127 x 96 x 74 mm, 650 g

Going beyond this snapshot of core features and characteristics, what are the differences between the Leica SL (Typ 601) and the Sony Alpha A7R 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 Leica SL and the Sony A7R III is provided 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 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 A7R III is notably smaller (20 percent) than the Leica SL. Moreover, the A7R III is markedly lighter (23 percent) than the 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.

The power pack in the A7R III can be charged via the USB port, 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. If you want to switch the focus of the display and review another camera pair, just select a new right or left comparator from among the camera models in the table. Alternatively, you can also 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 1	Weather Sealing	Camera Launch 2	Launch Price (USD)	Street Price
	Leica SL	5.8 in	4.1 in	1.5 in	29.9 oz	400	Y	Oct 2015	7,450
	Sony A7R III	5.0 in	3.8 in	2.9 in	22.9 oz	650	Y	Oct 2017	3,199
	Canon 1D X Mark II	6.2 in	6.6 in	3.3 in	54.0 oz	1210	Y	Feb 2016	5,999
	Canon 80D	5.5 in	4.1 in	3.1 in	25.8 oz	960	Y	Feb 2016	1,199
	Canon 5DS	6.0 in	4.6 in	3.0 in	32.8 oz	700	Y	Feb 2015	3,699
	Leica SL2	5.7 in	4.2 in	1.7 in	33.6 oz	370	Y	Nov 2019	5,999
	Leica M10	5.5 in	3.1 in	1.5 in	23.3 oz	210	Y	Jan 2017	6,595
	Leica M Typ 240	5.5 in	3.1 in	1.7 in	24.0 oz	..	Y	Sep 2012	6,950
	Nikon Z7	5.3 in	4.0 in	2.6 in	23.8 oz	330	Y	Aug 2018	3,399
	Nikon D5	6.3 in	6.3 in	3.6 in	49.9 oz	3780	Y	Jan 2016	6,499
	Nikon D500	5.8 in	4.5 in	3.2 in	30.3 oz	1240	Y	Jan 2016	1,999
	Nikon D7200	5.4 in	4.2 in	3.0 in	27.0 oz	1110	Y	Mar 2015	1,199
	Nikon D750	5.6 in	4.4 in	3.1 in	26.5 oz	1230	Y	Sep 2014	2,299
	Sony A9	5.0 in	3.8 in	2.5 in	23.7 oz	650	Y	Apr 2017	4,499
	Sony A99 II	5.6 in	4.1 in	3.0 in	29.9 oz	490	Y	Sep 2016	3,199
	Sony A7R II	5.0 in	3.8 in	2.4 in	22.0 oz	290	Y	Jun 2015	3,199
	Sony A7S II	5.0 in	3.8 in	2.4 in	22.1 oz	370	Y	Sep 2015	2,999
Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders. (1) Number of images that can be taken on a full battery charge according to the CIPA-standard; (2) Official announcement.

Camera Model
Leica SL
Sony A7R III
Canon 1D X Mark II
Canon 80D
Canon 5DS
Leica SL2
Leica M10
Leica M Typ 240
Nikon Z7
Nikon D5
Nikon D500
Nikon D7200
Nikon D750
Sony A9
Sony A99 II
Sony A7R II
Sony A7S II

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. The A7R III was launched at a markedly lower price (by 57 percent) than the SL, 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. 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. All other things equal, a large sensor will have larger individual pixel-units that offer better low-light sensitivity, wider dynamic range, and 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 associated with larger, more expensive camera bodies and lenses.

Both cameras under consideration feature a full frame sensor, but their sensors differ slightly in size. 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.

Despite having a slightly smaller sensor, the A7R III offers a higher resolution of 42.2 megapixels, compared with 24 MP of the SL. This megapixels advantage comes at the cost of a higher pixel density and a smaller size of the individual pixel (with a pixel pitch of 4.52μm versus 6.00μm for the SL). However, it should be noted that the A7R III is much more recent (by 2 years) than the SL, and its sensor will have benefitted from technological advances during this time that make it possible to gather light more efficiently. Coming back to sensor resolution, it should be mentioned that neither of the two cameras has an anti-alias filter installed, so they are able to capture all the detail the sensor resolves.

The resolution advantage of the Sony A7R III implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the A7R III for good quality output (200 dots per inch) amounts to 39.8 x 26.5 inches or 101 x 67.4 cm, for very good quality (250 dpi) 31.8 x 21.2 inches or 80.8 x 53.9 cm, and for excellent quality (300 dpi) 26.5 x 17.7 inches or 67.3 x 44.9 cm. The corresponding values for the Leica SL are 30 x 20 inches or 76.2 x 50.8 cm for good quality, 24 x 16 inches or 61 x 40.6 cm for very good quality, and 20 x 13.3 inches or 50.8 x 33.9 cm for excellent quality prints.

The A7R III has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

Unlike the SL, the A7R III 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 Leica SL (Typ 601) has a native sensitivity range from ISO 50 to ISO 50000. The corresponding ISO settings for the Sony Alpha A7R III are ISO 100 to ISO 32000, with the possibility to increase the ISO range to 50-102400.

For many cameras, data on sensor performance has been reported by DXO Mark. 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"). Of the two cameras under consideration, the A7R III offers substantially better image quality than the SL (overall score 12 points higher). The advantage is based on 1 bits higher color depth, 1.3 EV in additional dynamic range, and 1 stops in additional low light sensitivity. 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
	Leica SL	Full Frame	24.0	6000	4000	4K/30p	25.0	13.4	1821	88
	Sony A7R III	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
	Canon 1D X Mark II	Full Frame	20.0	5472	3648	4K/60p	24.1	13.5	3207	88
	Canon 80D	APS-C	24.0	6000	4000	1080/60p	23.6	13.2	1135	79
	Canon 5DS	Full Frame	50.3	8688	5792	1080/30p	24.7	12.4	2381	87
	Leica SL2	Full Frame	46.7	8368	5584	4K/60p	..	..	..	..
	Leica M10	Full Frame	23.8	5952	3992	none	24.4	13.2	2133	86
	Leica M Typ 240	Full Frame	23.7	5952	3976	1080/25p	24.0	13.3	1860	84
	Nikon Z7	Full Frame	45.4	8256	5504	4K/30p	26.3	14.6	2668	99
	Nikon D5	Full Frame	20.7	5588	3712	4K/30p	25.1	12.3	2343	88
	Nikon D500	APS-C	20.7	5568	3712	4K/30p	24.0	14.0	1324	83
	Nikon D7200	APS-C	24.0	6000	4000	1080/60p	24.5	14.6	1333	87
	Nikon D750	Full Frame	24.2	6016	4016	1080/60p	24.8	14.5	2956	93
	Sony A9	Full Frame	24.0	6000	4000	4K/30p	24.9	13.3	3517	92
	Sony A99 II	Full Frame	42.2	7952	5304	4K/30p	25.4	13.4	2317	92
	Sony A7R II	Full Frame	42.2	7952	5304	4K/30p	26.0	13.9	3434	98
	Sony A7S II	Full Frame	12.0	4240	2832	4K/30p	23.6	13.3	2993	85

Camera Model
Leica SL
Sony A7R III
Canon 1D X Mark II
Canon 80D
Canon 5DS
Leica SL2
Leica M10
Leica M Typ 240
Nikon Z7
Nikon D5
Nikon D500
Nikon D7200
Nikon D750
Sony A9
Sony A99 II
Sony A7R II
Sony A7S II

Many modern cameras are not only capable of taking still images, but can also record movies. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, and both provide the same movie specifications (4K/30p).

Feature comparison

Apart from body and sensor, cameras can and do differ across a range of features. The two cameras under consideration are similar with respect to both having an electronic viewfinder. However, the one in the SL offers a higher resolution than the one in the A7R III (4400k vs 3686k dots). The adjacent table lists some of the other core features of the Leica SL and Sony A7R III along with similar information for a selection of comparators.

Core Features

	Camera Model	Viewfinder (Type or 000 dots)	Control Panel (yes/no)	LCD Size (inch)	LCD Resolution (000 dots)	LCD Attach- ment	Touch Screen (yes/no)	Mech Shutter Speed	Shutter Flaps (1/sec)	Built-in Flash (yes/no)	Built-in Image Stab
	Leica SL	4400	Y	3.0	1040	fixed	Y	1/8000s	11.0	n	n
	Sony A7R III	3686	n	3.0	1440	tilting	Y	1/8000s	10.0	n	Y
	Canon 1D X Mark II	optical	Y	3.2	1620	fixed	Y	1/8000s	16.0	n	n
	Canon 80D	optical	Y	3.0	1040	swivel	Y	1/8000s	7.0	Y	n
	Canon 5DS	optical	Y	3.2	1040	fixed	n	1/8000s	5.0	n	n
	Leica SL2	5760	Y	3.2	2100	fixed	Y	1/8000s	10.0	n	Y
	Leica M10	optical	n	3.0	1037	fixed	n	1/4000s	5.0	n	n
	Leica M Typ 240	optical	n	3.0	920	fixed	n	1/4000s	3.0	n	n
	Nikon Z7	3690	Y	3.2	2100	tilting	Y	1/8000s	9.0	n	Y
	Nikon D5	optical	Y	3.2	2359	fixed	Y	1/8000s	14.0	n	n
	Nikon D500	optical	Y	3.2	2359	tilting	Y	1/8000s	10.0	n	n
	Nikon D7200	optical	Y	3.2	1229	fixed	n	1/8000s	6.0	Y	n
	Nikon D750	optical	Y	3.2	1229	tilting	n	1/4000s	6.0	Y	n
	Sony A9	3686	n	3.0	1440	tilting	Y	1/8000s	20.0	n	Y
	Sony A99 II	2400	Y	3.0	1229	full-flex	n	1/8000s	12.0	n	Y
	Sony A7R II	2400	n	3.0	1229	tilting	n	1/8000s	5.0	n	Y
	Sony A7S II	2400	n	3.0	1229	tilting	n	1/8000s	5.0	n	Y

Camera Model
Leica SL
Sony A7R III
Canon 1D X Mark II
Canon 80D
Canon 5DS
Leica SL2
Leica M10
Leica M Typ 240
Nikon Z7
Nikon D5
Nikon D500
Nikon D7200
Nikon D750
Sony A9
Sony A99 II
Sony A7R II
Sony A7S II

One feature that is present on the SL, but is missing on the A7R 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 A7R 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 SL writes its imaging data to SDXC cards, while the A7R III uses SDXC or Memory Stick PRO Duo cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. Both the SL and the A7R III support UHS-II cards (Ultra High Speed data transfer of up to 312 MB/s) on the first slot and UHS-I cards (104 MB/s) on the second one.

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 A7R 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 Microphone	Internal Speaker	Microphone Port	Headphone Port	HDMI Port	USB Port	WiFi Support	NFC Support	Bluetooth Support
	Leica SL	Y	stereo	mono	Y	Y	full	3.0	Y	-	-
	Sony A7R III	Y	stereo	mono	Y	Y	micro	3.1	Y	Y	Y
	Canon 1D X Mark II	Y	mono	mono	Y	Y	mini	3.0	-	-	-
	Canon 80D	Y	stereo	mono	Y	Y	mini	2.0	Y	Y	-
	Canon 5DS	Y	mono	mono	Y	-	mini	3.0	-	-	-
	Leica SL2	Y	stereo	mono	Y	Y	full	3.1	Y	-	Y
	Leica M10	Y	-	-	-	-	-	-	Y	-	-
	Leica M Typ 240	Y	stereo	mono	-	-	-	2.0	-	-	-
	Nikon Z7	Y	stereo	mono	Y	Y	micro	3.1	Y	-	Y
	Nikon D5	Y	stereo	mono	Y	Y	mini	3.0	-	-	-
	Nikon D500	Y	stereo	mono	Y	Y	mini	3.0	Y	Y	Y
	Nikon D7200	Y	stereo	mono	Y	Y	mini	2.0	Y	Y	-
	Nikon D750	Y	stereo	mono	Y	Y	mini	2.0	Y	-	-
	Sony A9	Y	stereo	mono	Y	Y	micro	2.0	Y	Y	Y
	Sony A99 II	Y	stereo	mono	Y	Y	micro	2.0	Y	Y	Y
	Sony A7R II	Y	stereo	mono	Y	Y	micro	2.0	Y	Y	-
	Sony A7S II	Y	stereo	mono	Y	Y	micro	2.0	Y	Y	-

Camera Model
Leica SL
Sony A7R III
Canon 1D X Mark II
Canon 80D
Canon 5DS
Leica SL2
Leica M10
Leica M Typ 240
Nikon Z7
Nikon D5
Nikon D500
Nikon D7200
Nikon D750
Sony A9
Sony A99 II
Sony A7R II
Sony A7S II

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 SL has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.

Both the SL and the A7R III have been discontinued, but can regularly be found used on eBay. The SL was replaced by the Leica SL2, while the A7R III was followed by the Sony A7R IV. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Leica and Sony websites.

Review summary

So what is the bottom line? Is the Leica SL better than the Sony A7R III or vice versa? Below is a summary of the relative strengths of each of the two contestants.

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

• More detailed viewfinder: Has higher resolution electronic viewfinder (4400k vs 3686k dots).
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.80x vs 0.78x).
• 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 solid recording: Has a full-sized HDMI port for a sturdy connection to an external recorder.
• 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).

Advantages of the Sony Alpha A7R III:

• More detail: Has more megapixels (42.2 vs 24MP), which boosts linear resolution by 33%.
• High quality composites: Can combine several shots after pixel-shifting its sensor.
• Better image quality: Scores substantially higher (12 points) in the DXO overall evaluation.
• More dynamic range: Captures a broader range of light and dark details (1.3 EV of extra DR).
• Better low-light sensitivity: Can shoot in dim conditions (1 stops ISO advantage).
• Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
• More detailed LCD: Has a higher resolution rear screen (1440k vs 1040k dots).
• More flexible LCD: Has a tilting screen for odd-angle shots in landscape orientation.
• More compact: Is smaller (127x96mm vs 147x104mm) and will fit more readily into a bag.
• Less heavy: Has a lower weight (by 197g or 23 percent) and is thus easier to take along.
• Longer lasting: Gets more shots (650 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 device pairing: Supports NFC for fast wireless image transfer over short distances.
• Easier wireless transfer: Supports Bluetooth for image sharing without cables.
• More affordable: Was introduced into a lower priced category (57 percent cheaper at launch).
• More modern: Reflects 2 years of technical progress since the SL launch.

If the number of relative strengths (bullet points above) is taken as a guide, the A7R III is the clear winner of the contest (16 : 7 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 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 Leica SL and the Sony A7R 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 SL or the A7R III. 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 table below provides a synthesis of the camera assessments of some of the best known photo-gear review sites (cameralabs, dpreview, ephotozine, imaging-resource, and photographyblog). 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.

Review Scores

	Camera Model	camera   labs	dp review	ephoto   zine	imaging resource	photography   blog	Camera Launch	Launch Price (USD)	Street Price
	Leica SL	..	84/100	4.5/5	4/5	4/5	Oct 2015	7,450
	Sony A7R III	+ +	90/100	4.5/5	5/5	5/5	Oct 2017	3,199
	Canon 1D X Mark II	..	89/100	4.5/5	5/5	4.5/5	Feb 2016	5,999
	Canon 80D	+ +	84/100	4.5/5	4.5/5	4.5/5	Feb 2016	1,199
	Canon 5DS	+	83/100	4.5/5	5/5	4.5/5	Feb 2015	3,699
	Leica SL2	..	..	4.5/5	..	4/5	Nov 2019	5,999
	Leica M10	..	..	4/5	..	4.5/5	Jan 2017	6,595
	Leica M Typ 240	..	..	4/5	..	..	Sep 2012	6,950
	Nikon Z7	+	89/100	4.5/5	4.5/5	5/5	Aug 2018	3,399
	Nikon D5	..	89/100	4.5/5	5/5	5/5	Jan 2016	6,499
	Nikon D500	+ +	91/100	4.5/5	5/5	5/5	Jan 2016	1,999
	Nikon D7200	+ +	84/100	4.5/5	4/5	4.5/5	Mar 2015	1,199
	Nikon D750	+ +	90/100	4.5/5	5/5	4.5/5	Sep 2014	2,299
	Sony A9	+ +	89/100	5/5	5/5	5/5	Apr 2017	4,499
	Sony A99 II	..	85/100	4.5/5	4.5/5	4.5/5	Sep 2016	3,199
	Sony A7R II	+ +	90/100	5/5	4.5/5	5/5	Jun 2015	3,199
	Sony A7S II	+	..	4.5/5	5/5	5/5	Sep 2015	2,999
Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

Camera Model
Leica SL
Sony A7R III
Canon 1D X Mark II
Canon 80D
Canon 5DS
Leica SL2
Leica M10
Leica M Typ 240
Nikon Z7
Nikon D5
Nikon D500
Nikon D7200
Nikon D750
Sony A9
Sony A99 II
Sony A7R II
Sony A7S II

The review scores listed above should be treated with care, though. The assessments were made in relation to similar cameras of the same technological generation. Thus, a score needs to be put into the context of the launch date and the launch price of the camera, 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.

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 make a corresponding selection in the search boxes below. As an alternative, you can also directly jump to any one of the listed comparisons that were previously generated by the CAM-parator tool.

Specifications: Leica SL vs Sony A7R III

Below is a side-by-side comparison of the specs of the two cameras to facilitate a quick review of their differences and common features.

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