Nikon D750 vs Sony A9
The Nikon D750 and the Sony Alpha A9 are two digital cameras that were revealed to the public, respectively, in September 2014 and April 2017. The D750 is a DSLR, while the A9 is a mirrorless interchangeable lens camera. Both cameras are equipped with a full frame sensor. The Nikon has a resolution of 24.2 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.
|Nikon D750||Sony A9|
|Digital single lens reflex||Mirrorless system camera|
|Nikon F mount lenses||Sony E mount lenses|
|24.2 MP, Full Frame Sensor||24 MP, Full Frame Sensor|
|1080/60p Video||4K/30p Video|
|ISO 100-12800 (50-51200)||ISO 100-51200 (50-204800)|
|Optical viewfinder||Electronic viewfinder (3686k dots)|
|3.2" LCD, 1229k dots||3.0" LCD, 1440k dots|
|Tilting screen (no touchscreen)||Tilting touchscreen|
|6 shutter flaps per second||20 shutter flaps per second|
|Lens stabilization only||In-body stabilization|
|Weathersealed body||Weathersealed body|
|1230 shots per battery charge||650 shots per battery charge|
|141 x 113 x 78 mm, 750 g||127 x 96 x 63 mm, 673 g|
Going beyond this snapshot of core features and characteristics, what are the differences between the Nikon D750 and the Sony Alpha A9? 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.
The side-by-side display below illustrates the physical size and weight of the Nikon D750 and the Sony A9. The two cameras are presented according to their relative size. Three successive views from the front, the top, and the rear are shown. All width, height and depth measures 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 is notably smaller (23 percent) than the Nikon D750. Moreover, the A9 is markedly lighter (10 percent) than the D750. 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. Both cameras have similarly sized sensors, but DSLRs have a larger flange-to-focal plane distance than mirrorless cameras, which imposes contraints on the optical engineering process and generally leads to bigger and heavier lenses. You can compare the optics available for the two cameras in the Nikon Lens Catalog (D750) and the Sony FE Lens Catalog (A9). Mirrorless cameras, such as the A9, have moreover the advantage that they can use many lenses from other systems via adapters, as they have a relatively short flange to focal plane distance.
Concerning battery life, the D750 gets 1230 shots out of its EN-EL15 battery, while the A9 can take 650 images on a single charge of its NP-FZ100 power pack. The power pack in the A9 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. In case you want to display and compare another camera duo, just click on the right or left arrow next to the camera that you would like to inspect. Alternatively, you can also use the CAM-parator to select your camera combination among a larger number of options.
|Nikon D750»||141 mm||113 mm||78 mm||750 g||1230||Y||Sep 2014||2,299||Nikon D750|
|Sony A9«||127 mm||96 mm||63 mm||673 g||650||Y||Apr 2017||4,499||Sony A9|
|Canon 6D Mark II« »||144 mm||111 mm||75 mm||765 g||1200||Y||Jun 2017||1,999||Canon 6D Mark II|
|Nikon D780« »||144 mm||116 mm||76 mm||840 g||2260||Y||Jan 2020||2,299||Nikon D780|
|Nikon D7500« »||136 mm||104 mm||73 mm||720 g||950||Y||Apr 2017||1,299||Nikon D7500|
|Nikon D500« »||147 mm||115 mm||81 mm||860 g||1240||Y||Jan 2016||1,999||Nikon D500|
|Nikon D7200« »||136 mm||107 mm||76 mm||765 g||1110||Y||Mar 2015||1,199||Nikon D7200|
|Nikon D7100« »||136 mm||107 mm||76 mm||765 g||950||Y||Feb 2013||1,199||Nikon D7100|
|Nikon Df« »||144 mm||110 mm||67 mm||760 g||1400||Y||Nov 2013||2,749||Nikon Df|
|Nikon D610« »||141 mm||113 mm||82 mm||850 g||900||Y||Oct 2013||1,999||Nikon D610|
|Nikon D600« »||141 mm||113 mm||82 mm||850 g||900||Y||Sep 2012||2,099||Nikon D600|
|Nikon D700« »||147 mm||123 mm||77 mm||1074 g||1000||Y||Jul 2008||2,999||Nikon D700|
|Panasonic GH5« »||139 mm||98 mm||87 mm||725 g||410||Y||Jan 2017||1,999||Panasonic GH5|
|Sony A9 II« »||129 mm||96 mm||76 mm||678 g||690||Y||Oct 2019||4,499||Sony A9 II|
|Sony A7 III« »||127 mm||96 mm||74 mm||650 g||610||Y||Feb 2018||1,999||Sony A7 III|
|Sony A7R III« »||127 mm||96 mm||74 mm||650 g||650||Y||Oct 2017||3,199||Sony A7R III|
|Sony A7 II« »||127 mm||96 mm||60 mm||599 g||350||Y||Nov 2014||1,999||Sony A7 II|
|Note: Measurements and pricing do not include easily detachable parts, such as interchangeable lenses or optional viewfinders.|
The price is, of course, an important factor in any camera decision. The retail prices at the time of the camera’s release place the model in the market relative to other models in the producer’s line-up and the competition. The D750 was launched at a markedly lower price (by 49 percent) than the A9, 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.
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 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. The sensor area in the A9 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 24.2MP, the D750 offers a slightly higher resolution than the A9 (24MP), but the D750 nevertheless has marginally larger individual pixels (pixel pitch of 5.97μm versus 5.94μm for the A9) due to its larger sensor. However, the A9 is a much more recent model (by 2 years and 7 months) than the D750, and its sensor will have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixels.
The A9 has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.
The Nikon D750 has a native sensitivity range from ISO 100 to ISO 12800, which can be extended to ISO 50-51200. The corresponding ISO settings for the Sony Alpha A9 are ISO 100 to ISO 51200, with the possibility to increase the ISO range to 50-204800.
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.
|Nikon D750||Full Frame||24.2||6016||4016||1080/60p||24.8||14.5||2956||93||Nikon D750|
|Sony A9||Full Frame||24.0||6000||4000||4K/30p||24.9||13.3||3517||92||Sony A9|
|Canon 6D Mark II||Full Frame||26.0||6240||4160||1080/60p||24.4||11.9||2862||85||Canon 6D Mark II|
|Nikon D780||Full Frame||24.3||6048||4024||4K/30p||..||..||..||..||Nikon D780|
|Nikon D7500||APS-C||20.7||5568||3712||4K/30p||24.3||14.0||1483||86||Nikon D7500|
|Nikon D500||APS-C||20.7||5568||3712||4K/30p||24.0||14.0||1324||83||Nikon D500|
|Nikon D7200||APS-C||24.0||6000||4000||1080/60p||24.5||14.6||1333||87||Nikon D7200|
|Nikon D7100||APS-C||24.0||6000||4000||1080/60p||24.2||13.7||1256||83||Nikon D7100|
|Nikon Df||Full Frame||16.2||4928||3280||none||24.6||13.1||3279||89||Nikon Df|
|Nikon D610||Full Frame||24.2||6016||4016||1080/30p||25.1||14.4||2925||94||Nikon D610|
|Nikon D600||Full Frame||24.2||6016||4016||1080/30p||25.1||14.2||2980||94||Nikon D600|
|Nikon D700||Full Frame||12.1||4256||2832||none||23.5||12.2||2303||80||Nikon D700|
|Panasonic GH5||Four Thirds||20.2||5184||3888||4K/60p||23.9||13.0||807||77||Panasonic GH5|
|Sony A9 II||Full Frame||24.0||6000||4000||4K/30p||25.0||14.0||3434||93||Sony A9 II|
|Sony A7 III||Full Frame||24.0||6000||4000||4K/30p||25.0||14.7||3730||96||Sony A7 III|
|Sony A7R III||Full Frame||42.2||7952||5304||4K/30p||26.0||14.7||3523||100||Sony A7R III|
|Sony A7 II||Full Frame||24.0||6000||4000||1080/60p||24.9||13.6||2449||90||Sony A7 II|
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 A9 provides a better video resolution than the D750. It can shoot movie footage at 4K/30p, while the Nikon is limited to 1080/60p.
Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A9 has an electronic viewfinder (3686k dots), while the D750 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 A9 has a higher magnification than the one of the D750 (0.78x vs 0.70x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The following table reports on some other key feature differences and similarities of the Nikon D750, the Sony A9, and comparable cameras.
|Nikon D750||optical||Y||3.2||1229||tilting||n||1/4000s||6.0||Y||n||Nikon D750|
|Sony A9||3686||n||3.0||1440||tilting||Y||1/8000s||20.0||n||Y||Sony A9|
|Canon 6D Mark II||optical||Y||3.0||1040||swivel||Y||1/4000s||6.5||n||n||Canon 6D Mark II|
|Nikon D780||optical||Y||3.2||2359||tilting||Y||1/8000s||12.0||n||n||Nikon D780|
|Nikon D7500||optical||Y||3.2||922||tilting||Y||1/8000s||8.0||Y||n||Nikon D7500|
|Nikon D500||optical||Y||3.2||2359||tilting||Y||1/8000s||10.0||n||n||Nikon D500|
|Nikon D7200||optical||Y||3.2||1229||fixed||n||1/8000s||6.0||Y||n||Nikon D7200|
|Nikon D7100||optical||Y||3.2||1229||fixed||n||1/8000s||6.0||Y||n||Nikon D7100|
|Nikon Df||optical||Y||3.2||921||fixed||n||1/4000s||5.5||n||n||Nikon Df|
|Nikon D610||optical||Y||3.2||921||fixed||n||1/4000s||6.0||Y||n||Nikon D610|
|Nikon D600||optical||Y||3.0||921||fixed||n||1/4000s||5.5||Y||n||Nikon D600|
|Nikon D700||optical||Y||3.0||922||fixed||n||1/8000s||8.0||Y||n||Nikon D700|
|Panasonic GH5||3680||n||3.2||1620||swivel||Y||1/8000s||12.0||n||Y||Panasonic GH5|
|Sony A9 II||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y||Sony A9 II|
|Sony A7 III||2359||n||3.0||922||tilting||Y||1/8000s||10.0||n||Y||Sony A7 III|
|Sony A7R III||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y||Sony A7R III|
|Sony A7 II||2400||n||3.0||1230||tilting||n||1/8000s||5.0||n||Y||Sony A7 II|
One difference between the cameras concerns the presence of an on-board flash. The D750 has one, while the A9 does not. While the built-in flash of the D750 is not very powerful, it can at times be useful as a fill-in light.
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 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 Nikon D750 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 D750 writes its imaging data to SDXC cards, while the A9 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. The A9 supports UHS-II cards (on its first slot), while the D750 can use UHS-I cards.
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 Nikon D750 and Sony Alpha A9 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
|Nikon D750||Y||stereo||mono||Y||Y||mini||2.0||Y||-||-||Nikon D750|
|Sony A9||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||Y||Sony A9|
|Canon 6D Mark II||Y||stereo||mono||Y||-||mini||2.0||Y||Y||Y||Canon 6D Mark II|
|Nikon D780||Y||stereo||mono||Y||Y||mini||3.1||Y||-||Y||Nikon D780|
|Nikon D7500||Y||stereo||mono||Y||Y||mini||2.0||Y||-||Y||Nikon D7500|
|Nikon D500||Y||stereo||mono||Y||Y||mini||3.0||Y||Y||Y||Nikon D500|
|Nikon D7200||Y||stereo||mono||Y||Y||mini||2.0||Y||Y||-||Nikon D7200|
|Nikon D7100||Y||stereo||mono||Y||Y||mini||2.0||-||-||-||Nikon D7100|
|Nikon Df||Y||none||none||-||-||mini||2.0||-||-||-||Nikon Df|
|Nikon D610||Y||mono||mono||Y||Y||mini||2.0||-||-||-||Nikon D610|
|Nikon D600||Y||mono||mono||Y||Y||mini||2.0||-||-||-||Nikon D600|
|Nikon D700||Y||none||none||-||-||mini||2.0||-||-||-||Nikon D700|
|Panasonic GH5||Y||stereo||mono||Y||Y||full||3.1||Y||-||Y||Panasonic GH5|
|Sony A9 II||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y||Sony A9 II|
|Sony A7 III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y||Sony A7 III|
|Sony A7R III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y||Sony A7R III|
|Sony A7 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-||Sony A7 II|
Both cameras feature a PC Sync terminal to control professional strobe lights, which will be appreciated by studio photographers.
Both the D750 and the A9 have been discontinued, but can regularly be found used on eBay. The D750 was replaced by the Nikon D780, while the A9 was followed by the Sony A9 II. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Nikon and Sony websites.
So what is the bottom line? Is the Nikon D750 better than the Sony A9 or vice versa? The listing below highlights the relative strengths of the two models.
Reasons to prefer the Nikon D750:
- More dynamic range: Captures a larger spectrum of light and dark details (1.2 EV of extra DR).
- Brighter framing: Features an optical viewfinder for clear, lag-free composition.
- Easier setting verification: Features an LCD display on top to control shooting parameters.
- Larger screen: Has a bigger rear LCD (3.2" vs 3.0") for image review and settings control.
- Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
- Longer lasting: Can take more shots (1230 versus 650) on a single battery charge.
- Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
- More affordable: Was introduced into a lower priced category (49 percent cheaper at launch).
- More heavily discounted: Has been available for much longer (launched in September 2014).
Arguments in favor of the Sony Alpha A9:
- Better video: Provides higher definition movie capture (4K/30p vs 1080/60p).
- Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
- More framing info: Has an electronic viewfinder that displays shooting data.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.78x vs 0.70x).
- More detailed LCD: Has a higher resolution rear screen (1440k vs 1229k dots).
- Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
- Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
- Faster burst: Shoots at higher frequency (20 vs 6 flaps/sec) to capture the decisive moment.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- More compact: Is smaller (127x96mm vs 141x113mm) and will fit more readily into a bag.
- 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.
- More legacy lens friendly: Can use many non-native lenses via adapters.
- Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
- Easier wireless transfer: Supports Bluetooth for image sharing without cables.
- Faster buffer clearing: Supports a more advanced SD data transfer standard (UHS-II vs UHS-I).
- More modern: Reflects 2 years and 7 months of technical progress since the D750 launch.
If the count of relative strengths (bullet points above) is taken as a measure, the A9 is the clear winner of the contest (16 : 9 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 Nikon D750 and the Sony A9 place the cameras among the top in their class? Find out in the latest Best DSLR Camera and Best Mirrorless Interchangeable Lens Camera listings 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 D750 and the A9 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.
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 (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.
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 comparisons of ratings among very different cameras or across long time periods have little meaning. It should also be noted that some of the review sites have over time altered the way they render their verdicts.
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.
Specifications: Nikon D750 vs Sony A9
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.
|Camera Model||Nikon D750||Sony A9|
|Camera Type||Digital single lens reflex||Mirrorless system camera|
|Camera Lens||Nikon F mount lenses||Sony E mount lenses|
|Launch Date||September 2014||April 2017|
|Launch Price||USD 2299||USD 4499|
|Sensor Specs||Nikon D750||Sony A9|
|Sensor Format||Full Frame Sensor||Full Frame Sensor|
|Sensor Size||35.9 x 24.0 mm||35.6 x 23.8 mm|
|Sensor Area||861.6 mm2||847.28 mm2|
|Sensor Diagonal||43.2 mm||42.8 mm|
|Sensor Resolution||24.2 Megapixels||24 Megapixels|
|Image Resolution||6016 x 4016 pixels||6000 x 4000 pixels|
|Pixel Pitch||5.97 μm||5.94 μm|
|Pixel Density||2.80 MP/cm2||2.83 MP/cm2|
|Moiré control||Anti-Alias filter||Anti-Alias filter|
|Movie Capability||1080/60p Video||4K/30p Video|
|ISO Setting||100-12800 ISO||100-51200 ISO|
|ISO Boost||50-51200 ISO||50-204800 ISO|
|Image Processor||EXPEED 4||BIONZ X|
|DXO Sensor Quality (score)||93||92|
|DXO Color Depth (bits)||24.8||24.9|
|DXO Dynamic Range (EV)||14.5||13.3|
|DXO Low Light (ISO)||2956||3517|
|Screen Specs||Nikon D750||Sony A9|
|Viewfinder Type||Optical viewfinder||Electronic viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||3686k dots|
|Top-Level Screen||Control Panel||no Top Display|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.2 inch||3.0 inch|
|LCD Resolution||1229k dots||1440k dots|
|LCD Attachment||Tilting screen||Tilting screen|
|Touch Input||no Touchscreen||Touchscreen|
|Shooting Specs||Nikon D750||Sony A9|
|Focus System||Phase-detect AF||On-Sensor Phase-detect|
|Manual Focusing Aid||No Peaking Feature||Focus Peaking|
|Max Shutter Speed (mechanical)||1/4000/s||1/8000/s|
|Continuous Shooting||6 shutter flaps/s||20 shutter flaps/s|
|Shutter Life Expectancy||150 000 actuations||500 000 actuations|
|Electronic Shutter||no E-Shutter||up to 1/32000s|
|Time-Lapse Photography||Intervalometer built-in||no Intervalometer|
|Image Stabilization||Lens stabilization only||In-body stabilization|
|Fill Flash||Build-in Flash||no On-Board Flash|
|Storage Medium||SDXC cards||MS or SDXC cards|
|Second Storage Option||Dual card slots||Dual card slots|
|UHS card support||UHS-I||Single UHS-II|
|Connectivity Specs||Nikon D750||Sony A9|
|Studio Flash||PC Sync socket||PC Sync socket|
|USB Connector||USB 2.0||USB 2.0|
|HDMI Port||mini HDMI||micro HDMI|
|Microphone Port||External MIC port||External MIC port|
|Headphone Socket||Headphone port||Headphone port|
|Wifi Support||Wifi built-in||Wifi built-in|
|Near-Field Communication||no NFC||NFC built-in|
|Bluetooth Support||no Bluetooth||Bluetooth built-in|
|Body Specs||Nikon D750||Sony A9|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||1230 shots per charge||650 shots per charge|
|In-Camera Charging||no USB charging||USB charging|
141 x 113 x 78 mm
(5.6 x 4.4 x 3.1 in)
127 x 96 x 63 mm
(5.0 x 3.8 x 2.5 in)
|Camera Weight||750 g (26.5 oz)||673 g (23.7 oz)|
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