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Sony α6400 Camera Review

Tested using Methodology v0.12.1
Review updated Apr 22, 2024 at 05:15 pm
Latest change: Writing modified Jan 29, 2024 at 09:10 am
Sony α6400 Picture
8.2
Travel Photography
8.1
Landscape Photography
7.5
Sport & Wildlife Photography
7.9
Raw Photo Performance
7.3
Vlogging
7.3
Studio Video
5.6
Action Video

First released in 2019, the Sony α6400 is the middle child in Sony's entry-level APS-C Alpha lineup, sitting above the Sony α6100 and below the Sony α6600. Performance-wise, all three are similar, with the same high-res APS-C sensor and Sony's class-leading Real-Time Tracking autofocus. This model is a good middle-ground option, offering better build quality and a higher-resolution EVF than the a6100, but missing the longer battery life and in-body image stabilization of the a6600.

Our Verdict

8.2 Travel Photography

The Sony a6400 is great for travel photography. It's relatively portable and well-built, with some weather-sealing for more peace of mind when shooting outdoors. Battery life is also quite good relative to other mirrorless cameras. Image quality is generally great, as well, and it's equipped with an excellent autofocus system that can track subjects without issue. That said, its ergonomics and user interface aren't the most intuitive.

Pros
  • Excellent overall autofocus performance.
  • Great photo quality.
  • Sturdy, portable design.
Cons
  • Ergonomics are somewhat lacking.
  • Interface isn't especially user-friendly.
8.1 Landscape Photography

The Sony a6400 is great for landscape photography, especially if you're looking for a more portable APS-C camera. It's sturdily built, relatively portable, and weather-sealed, which is good for outdoor shooting sessions at remote locations. Image quality is also impressive overall, with great dynamic range to bring out a wider array of highlight and shadow detail in high-contrast landscapes. However, its user interface isn't especially intuitive.

Pros
  • Great photo quality.
  • Sturdy, portable design.
  • Impressive dynamic range.
Cons
  • Ergonomics are somewhat lacking.
  • Interface isn't especially user-friendly.
7.5 Sport & Wildlife Photography

The Sony a6400 is good for casual sports and wildlife photography. Image quality is impressive, and it has a responsive and fairly reliable autofocus system that does a good job of keeping up with fast-moving subjects. It also shoots at a fairly quick max burst rate to capture sequential moments of fast action. That said, while it has a decently sized buffer, it takes a long time to clear if you manage to fill it up, which can slow you down considerably.

Pros
  • Relatively quick burst rate.
  • Excellent overall autofocus performance.
  • Great photo quality.
  • Sturdy, portable design.
Cons
  • Ergonomics are somewhat lacking.
  • Interface isn't especially user-friendly.
  • Long buffer clearing time.
7.9 Raw Photo Performance

The Sony a6400 has very good RAW image quality. With impressive dynamic range, it captures a wide range of detail in high-contrast scenes. Images look sharp and detailed, thanks to the camera's high-resolution sensor. Its noise handling is also decent in low light, though you'll still see noise in very low light.

Pros
  • Impressive dynamic range.
  • Images look sharp and detailed.
Cons
7.3 Vlogging

The Sony a6400 is decent for vlogging. Its screen can be flipped up to help you monitor yourself while recording, but unlike a fully articulated screen, it's easily blocked by peripherals like a microphone on the hot shoe. While video quality is good overall, there's a pretty heavy rolling shutter effect, which can cause skewing in the background with quicker camera movements. It also doesn't have in-body image stabilization, so you have to rely on optically stabilized lenses to get less shaky footage.

Pros
  • Excellent overall autofocus performance.
  • Sturdy, portable design.
  • Good video quality.
Cons
  • Disappointing video stabilization performance.
  • Screen can be blocked by hotshoe-mounted accessories.
  • Noticeable rolling shutter distortion.
7.3 Studio Video

The Sony a6400 is decent for studio video. Recording quality is impressive, but there are no high frame rate options in 4k to add slow-motion flourishes. It's also limited to 8-bit recording, even when outputting video to an external recorder, giving you less leeway to edit and grade your footage. On the upside, its autofocus system does an excellent job of tracking moving subjects and keeping them in focus. It also doesn't have a recording time limit, which is good for recording longer takes. While it has a microphone input, there's no headphone jack, which is a little disappointing.

Pros
  • Excellent overall autofocus performance.
  • Good video quality.
  • No recording time limit.
Cons
  • Limited to 8-bit color depth.
  • Noticeable rolling shutter distortion.
  • No headphone jack.
5.6 Action Video

The Sony Alpha 6400 isn't designed for POV action video. There are few frame rate options in 4k and it doesn't have built-in stabilization. It's sturdy, relatively compact, and weather-sealed, which is good for outdoor recording, but it isn't rugged or waterproof for more extreme action sports.

Pros
  • Sturdy, portable design.
Cons
  • Disappointing video stabilization performance.
  • Limited frame rate options in 4k.
  • Noticeable rolling shutter distortion.
  • 8.2 Travel Photography
  • 8.1 Landscape Photography
  • 7.5 Sport & Wildlife Photography
  • 7.9 Raw Photo Performance
  • 7.3 Vlogging
  • 7.3 Studio Video
  • 5.6 Action Video
  1. Updated Jan 29, 2024: Added text to the 'Raw Photo Performance' verdict box.
  2. Updated Jan 29, 2024: Converted to Test Bench 0.12.1.
  3. Updated Sep 07, 2023: We've updated the 'Sensor Type' from 'Exmor CMOS' to 'CMOS' to reflect the general sensor type without Sony-specific terminology.
  4. Updated Aug 30, 2023: Added link to the Canon EOS R10 in the '4k Video Internal Recording' section of the review to provide an alternative that supports 10-bit 4:2:2 internal recording.
  5. Updated Apr 05, 2023: Converted to Test Bench 0.12.
  6. Updated Feb 24, 2023: Added full text and rewrote existing text for clarity.
  7. Updated Feb 14, 2023: This camera's dimensions were slightly off, so we re-measured them and updated the values on the review. The score is unchanged.
  8. Updated Jan 23, 2023: Converted to Test Bench 0.11.
  9. Updated Sep 16, 2022: Converted to Test Bench 0.10.
  10. Updated Aug 04, 2022: Converted to Test Bench 0.9.
  11. Updated Apr 22, 2022: Converted to Test Bench 0.8.
  12. Updated Dec 22, 2021: Adjusted menu system score to be more in line with other Sony cameras we've tested.
  13. Updated Nov 08, 2021: Reprocessed and re-uploaded 4k and FHD video stabilization videos.
  14. Updated Jun 28, 2021: Retested object tracking performance for photography. Updated 'Autofocus' box accordingly.
  15. Updated Apr 29, 2021: Corrected input error in 'In The Box' section.
  16. Updated Apr 28, 2021: Retested for 'Tested Battery Life In Video' and updated score for 'Battery' section.
  17. Updated Feb 08, 2021: Review published.

Differences Between Sizes And Variants

The Sony Alpha 6400 comes in one color: 'Black'. You can see our unit's label here.

You can buy the body on its own, or bundled with a kit lens like the Sony E 16-50mm 3.5-5.6/PZ OSS lens or the Sony E 18-135mm f/3.5-5.6 OSS lens. 

If you come across a different variant of this camera, let us know in the discussions so we can update our review.

Compared To Other Cameras

The Sony a6400 is an entry-level camera with an APS-C sensor. It's relatively portable, well-built, and stands above the pack when it comes to autofocus performance. That said, its ergonomics leave something to be desired, and it uses the older version of Sony's user interface, which isn't the most intuitive. 

If you're looking for more options, check out our recommendations for the best mirrorless cameras for beginners, the best cameras under $1,000, and the best cameras for YouTube

Sony α6600

The Sony α6400 and the Sony α6600 are both APS-C cameras, and they perform similarly overall since they use the same sensor. The biggest difference between them is the inclusion of in-body image stabilization on the α6600, which can help stabilize the image at slower shutter speeds or longer focal lengths, even without an optically stabilized lens. The α6600 also has a larger battery that gives it nearly twice the rated battery life. However, the larger battery makes it bigger and heavier than the α6400. The α6600 also has a headphone jack and a couple more customizable buttons, though the α6400 has a built-in flash.

Sony α6100

The Sony α6400 is a bit better than the Sony α6100, though both cameras use the same sensor, providing similar image quality, and the same lens mount. Still, the α6400 has slightly better build quality, with some degree of weather-sealing and a higher-resolution EVF.

Sony ZV-E10

The Sony α6400 and the Sony ZV-E10 are both great mirrorless cameras for beginners. The α6400 is a little better suited for photography since it has a viewfinder, and it's a little more comfortable to shoot with and better built, with a weather-sealed magnesium alloy construction. The ZV-E10, on the other hand, is aimed specifically at vloggers and has a few advantages over the α6400 in that area, specifically a better built-in mic, an e-stabilization feature, and a fully articulated screen.

Sony α6000

The Sony α6400 is better overall than the Sony α6000, especially if you're interested in video as well as photography. The biggest difference is that the α6400 can record video in 4k resolution. It also has a higher-resolution EVF, a newer sensor with better high-ISO performance, and an improved autofocus system. The α6000 is a bit more portable and offers similar photo performance at a fraction of the price since it's an older model.

Sony α7 III

The Sony α7 III is better overall than the Sony α6400, though they use different-sized sensors. The biggest benefit of the α6400 is that it's more portable, but the α7 III is a higher-end and more capable camera, with a larger full-frame sensor, in-body image stabilization, and better ergonomics.

Sony α6700

The Sony α6700 is better than the Sony α6400. Beyond its new and improved sensor with a new processor, it's also better built, with a weather-sealed body, and has slightly better ergonomics. While image and video quality aren't far off, the α6700 has significantly better video specs, with internal 10-bit capture and more frame rate options.

Canon EOS M50

The Sony α6400 is better than the Canon EOS M50, primarily because Canon has discontinued its EF-M mount and is no longer developing new lenses for it. The Sony also has a more effective autofocus system, quicker burst shooting, and a longer battery life.

Nikon Z 50

The Nikon Z 50 and the Sony α6400 are both great entry-level models with different advantages. The Nikon has better ergonomics and a more intuitive user interface, while the Sony has a more effective autofocus system and a more established lens ecosystem.

Canon EOS R50

The Sony α6400 and the Canon EOS R50 are both good entry-level cameras. The Canon is significantly more portable and has a fully articulated screen, whereas the Sony uses a tilt-out screen. The Canon is slightly more accessible for beginners, with a more intuitive user interface and more extensive auto modes. The Canon also has somewhat more advanced internal video capabilities, with support for internal 10-bit capture and more frame rate options. On the flip side, the Sony offers a much more established lens lineup.

Canon EOS R10

The Sony α6400 and the Canon EOS R10 each have their advantages. The Sony's weather-sealed rangefinder-style body is more compact, can be recharged via USB-C without needing an additional power adapter, and has a larger photo buffer. Meanwhile, the R10 has a faster continuous shooting speed and a more robust range of video recording functionality: it can shoot uncropped 4k at 30 fps or cropped 4k at 60 fps. While only the Sony supports Log recording, it's limited to 8-bit color depth. You can contrast that with the Canon's HDR PQ profile, which allows for 10-bit 4:2:2 internal recording. The Canon's fully articulated display is also fully touch-sensitive and can be used to navigate its far more intuitive menu system.

Sony α7C

The Sony α7C is better than the Sony α6400, though they use different-sized sensors. The α7C's full-frame sensor outperforms the APS-C α6400 in dynamic range and low-light performance. It also features in-body image stabilization, a more effective autofocus system, and a longer battery life, but the α6400 is more portable.

Canon EOS M50 Mark II

The Sony α6400 is better than the Canon EOS M50 Mark II, as Canon has discontinued its EF-M mount and is no longer developing new lenses for it. On top of that, the Sony also has a more effective autofocus system, quicker burst shooting, and a longer battery life.

Canon EOS R100

The Sony α6400 is better overall than the Canon EOS R100, though the Canon may offer better value for those on a very tight budget or those looking for a simpler camera. The Sony has a less intuitive user interface, but it's better built, has a more effective autofocus system, quicker burst shooting, and better video specs.

Fujifilm X-T30 II

The Sony α6400 and the Fujifilm X-T30 II are both good mid-range cameras. They're both portable APS-C options, but while the Sony offers a more comfortable handgrip and better build quality, some shooters may prefer the retro style and dedicated exposure dials of the Fujifilm. Other than that, the Sony offers a more effective autofocus system for those who shoot a lot of moving subjects.

Nikon Z 30

The Nikon Z 30 and the Sony α6400 are both good entry-level cameras but have different strengths. The Nikon is better for vlogging, thanks to its fully articulated screen and uncropped 4k video recording at up to 30 fps. However, the Sony's viewfinder comes in handy for photography. It also has a better battery life and a more intuitive autofocus system. Lens options are more limited for the Nikon, as well.

Nikon Z fc

The Sony α6400 and the Nikon Z fc are both great entry-level APS-C cameras. That said, the Sony is a little more portable, feels a bit better built, and is more comfortable to shoot with. It also has a slightly more effective autofocus system and a better battery life. On the other hand, the Nikon has slightly better noise handling and dynamic range, along with a fully articulated screen that's better suited to vlogging and video work.

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Test Results

perceptual testing image
Design
7.9
Design
Portability
Height
2.9" (7.3 cm)
Width
5.0" (12.8 cm)
Depth
2.3" (5.9 cm)
Volume
33.6 in³ (551.3 cm³)
Weight
0.89 lbs (0.40 kg)

The Sony a6400 is quite portable. It's lightweight and has a relatively compact design that makes it easy to take on the go, especially compared to alternatives like the Nikon Z 50.

8.0
Design
Build Quality

Build quality is great overall. It's weather-sealed for some light protection against dust and moisture, with top and front pieces made of magnesium alloy. All in all, it feels durable, with sturdier materials than the all-plastic Sony a6100, though some of its dials can feel a bit sluggish.

Design
Body
Body Type
SLR-Style
Water Resistance
Weather-Sealed
Mirrorless
Yes
Rugged
No
Hot Shoe
Yes
Customizable Button
Yes
Command Dial
2
Tripod Mount
Yes
Lens Mount
E-Mount
Built-In Flash
Yes
Fastest Shutter Speed
1/4,000 s
Design
In The Box

  • Sony a6400 camera body
  • Sensor cap
  • Sony E 16-50mm 3.5-5.6/PZ OSS lens
  • Lens cap
  • Rear lens cover
  • Shoulder strap
  • 1x NP-FW50 battery
  • AC adapter
  • Micro-USB cable
  • Startup guide

8.0
Design
Ergonomics & Comfort
Hand Grip: Small Hand
Yes
Hand Grip: Medium Hand
Yes
Hand Grip: Large Hand
Yes
Hand Grip: Extra-Large Hand
No

The ergonomics are pretty good, and the camera should suit all but the largest hand sizes. It can feel a little cramped due to the camera's compact size, but the grip is nicely textured, and there are a fair amount of buttons and dials that make it relatively easy to adjust settings.

Design
Viewfinder
Viewfinder Type
Electronic
Advertised Coverage
100%
Advertised Resolution
2.36 million dots
Advertised Magnification
0.7

The EVF has a typical resolution for a mid-range mirrorless camera, though newer cameras have increasingly higher-res EVFs. Thankfully, the rubber eyecup around the viewfinder is fairly large and comfortable.

7.8
Design
Screen
Screen Articulation Type
Flip-Out
Screen Max Brightness
798 cd/m²
Advertised Resolution
0.92 million dots
Size
3.0" (7.5 cm)
Touchscreen
Limited

The Sony a6400 has a tilting screen. The tilting mechanism feels solid, and the screen gets plenty bright, so you'll still be able to see it on sunnier days. The resolution is a little on the low side, but it's still decently sharp. Unfortunately, touch capability is mostly limited to selecting focus points. You can't use it to navigate the menus, which is a bit of a hassle. For selfies and vlogs, you can flip the screen up 180 degrees to face you, but if you'd prefer a fully articulated screen, you can check out a camera like the Sony ZV-E10.

6.5
Design
Menu System
Guide Mode
Yes
App Name
Imaging Edge Mobile

The menu system is okay. Like other older Sony cameras, it's not particularly intuitive or clearly organized. There are many, many submenus and settings pages, and it can be a little difficult to find exactly what you're looking for. It doesn't help that you can't use the touchscreen to navigate through it. That said, there are a ton of customization options, including custom menus and a quick menu that makes it easier to find your most-accessed settings, once you set things to your liking.

not tested
Design
Built-In Lens
Maximum Aperture
No built-in lens
Max Aperture (Full-Frame Equivalent)
N/A
Minimum Focal Length
N/A
Maximum Focal Length
N/A
Max Focal Length (Full-Frame Equivalent)
N/A
Optical Image Stabilization
No
Luminance
N/A
Light Falloff
N/A
Design
Sensor
Sensor Type
CMOS
Advertised Effective Pixels
24.2 MP
Sensor Size
APS-C
Processor
BIONZ X
Extended ISO Minimum
N/A
Native ISO Minimum (Base ISO)
100
Native ISO Maximum
32,000
Tested Firmware
Version 2.0
7.8
Design
Battery
Battery Type
Sony NP-FW50
USB Charging
Yes
Power Delivery While Recording
Yes
Advertised Battery Life In Photo
410 photos
Tested Battery Life In Video
92 min

The Sony a6400 has good battery performance. It's rated for 410 shots by CIPA standards, which doesn't necessarily reflect real-world usage but is a good benchmark to see how cameras perform in relation to one another. It's quite good for an entry-level APS-C mirrorless camera, outperforming models like the Nikon Z 50 and the Fujifilm X-S10. But it still falls far short of DSLR standards and most full-frame mirrorless models.

Video battery life is decent. It can last for about an hour and a half of continuous 4k video recording at the camera's highest quality settings, which is fairly typical. You'll be able to record plenty of footage on a full charge, and it also supports use while charging over USB, if you need extra juice on a long shooting day.

Photo General
6.1
Photo General
Photo Shooting Speed
Low Speed Continuous
4 fps
High Speed Continuous
11 fps
Silent Shooting Continuous
8 fps
Raw Buffer Size
48 Photos
JPEG Buffer Size
108 Photos
Buffer Empty Time
25 s

The Sony a6400 shoots at a fairly quick max burst rate. It's fast enough for everyday sports and action photography, but the size of its buffer is somewhat limited. It's not the worst, but it can quickly fill up, especially if you're shooting RAW files. Unfortunately, it's also painfully slow to clear if you do manage to fill the buffer up, which can interrupt your shooting and potentially cause you to miss a critical moment.

7.9
Photo General
Photo AF-C Tracking
Autofocus Tracking Shots
Perfect Focus Hit Rate
66%
Usable Focus Hit Rate
85%

The Sony a6400 uses a hybrid autofocus system with both phase- and contrast-detection focus points. This generation of Alpha cameras have what Sony calls 'Real Time AF Tracking', which integrates the camera's subject detection with face and eye detection, so that the camera can seamlessly switch between them as the subject moves around. It works very intuitively and effectively, though the area mode options and settings can be a little overwhelming at first.

While the camera's tracking abilities don't surpass that of higher-end Sony cameras like the Sony a7C, it's still very good overall. If you rely on AF tracking, it keeps up with faster subjects well for the most part. Though focus points cover most of the frame, the camera can still lose track of people at the very edges. More erratic movements can also cause some trouble, but the camera is usually quick to re-acquire focus.

9.9
Photo General
Photo AF-C Center Point
Autofocus Center Point Shots
Perfect Focus Hit Rate
98%
Usable Focus Hit Rate
100%

With tracking disabled and sticking to single-point AF, the camera's autofocus is fantastic. It's accurate and quick, especially when using a lens with a solid focusing motor, and shouldn't have any trouble keeping whatever's under the focus point in focus.

7.8
Photo General
Photo Image Stabilization
Minimum Shutter Speed Achieved
1/13 s
In-Body Image Stabilization
No

Unlike the Sony a6600, the a6400 doesn't have in-body image stabilization, so you'll have to rely on optically stabilized lenses if you want to get steady shots at slower shutter speeds or longer focal lengths. Despite not having IBIS, Sony's Optical SteadyShot works well, and you can get clear photos at relatively slow shutter speeds when using a lens with OSS. That being said, stabilization performance can vary depending on the specific lens, what focal length you're shooting at, and even how steady your hands are.

Photo Image Quality
8.4
Photo Image Quality
Photo RAW Dynamic Range
Dynamic Range At Base ISO
10.7 f-stops
Dynamic Range At 1/500s Exposure Time
8.6 f-stops
Dynamic Range At 1/2000s Exposure Time
7.3 f-stops
Dynamic Range At 1/4000s Exposure Time
6.7 f-stops

The Sony a6400 has impressive dynamic range. It isn't as wide as cameras with full-frame sensors, but it still preserves a fairly wide range of highlight and shadow detail in high-contrast scenes. That drops off in low light, naturally, but it's on par with other APS-C cameras of its caliber.

8.3
Photo Image Quality
Photo RAW Sharpness
Vertical Edge MTF50 At Base ISO
1,910 LW/PH
Horizontal Edge MTF50 At Base ISO
1,919 LW/PH

Images are very detailed. With its high-resolution sensor, the camera does a great job of resolving fine detail, though this is most apparent when pixel-peeping. Still, you have a bit of leeway to crop in without losing too much clarity.

7.1
Photo Image Quality
Photo RAW Noise
SNR 18% At 1/8 Exposure Time (125 ms)
34.0dB
SNR 18% At 1/30 Exposure Time (33 ms)
30.8 dB
SNR 18% At 1/125 Exposure Time (8 ms)
25.8 dB
SNR 18% At 1/500 Exposure Time (2 ms)
20.2dB

The Sony a6400 has decent RAW noise handling. It performs well in low light for an APS-C camera, outperforming competitors like the Nikon Z 50.

Pictures Sample Gallery
Pictures Sample Gallery
The Skate Park Picture
JPEG Skate Park Picture Download
RAW Skate Park Picture Download
Pictures Sample Gallery
The Polish Church Picture
JPEG Polish Church Picture Download
RAW Polish Church Picture Download
Pictures Sample Gallery
The Studio Picture
JPEG Studio Picture Download
RAW Studio Picture Download
Pictures Sample Gallery
The Stairway Picture
JPEG Stairway Picture Download
RAW Stairway Picture Download
Video General
Video General
Video Features
Full HD Video
Yes
4k Video
Yes
6k Video
No
Clean HDMI Output
Yes
Advertised Max Chroma Sampling Over HDMI
4:2:2
Advertised Max Bit Depth Over HDMI
8 bits
Log Picture Profile
Yes
Recording Light
No

The Sony a6400 supports Log recording with S-Log 2 and S-Log 3 to preserve a wider range of detail in your videos, though it's limited to 8-bit color depth, so you'll have a harder time getting the most out of those Log profiles, especially S-Log 3.

Video General
Audio
Audio Test Sample
Audio Recording
Stereo
Microphone Level Display
Yes
Video General
Video File Format And Compression
MP4 H.264 / MPEG-4 AVC
No
MP4 H.265 / HEVC
No
MOV H.264 / MPEG-4 AVC
No
MOV H.265 / HEVC
No
AVCHD H.264 / MPEG-4 AVC
Yes
All-I Compression
No
4k Video
7.2
4k Video
4k Video Frame Rate
240 fps In 4k
No
120 fps In 4k
No
60 fps In 4k
No
30 fps In 4k
Yes, with a Crop
24 fps In 4k
Yes
4k Crop At Max Available fps
1.22 x

The camera is great for shooting more cinematic-looking videos at 24 fps, and it can also record 4k at 30 fps but with a noticeable crop. However, there aren't any high frame rate options for slow-motion video.

7.1
4k Video
4k Video Internal Recording
Bitrate Maximum In 4k
100 Mbps
Bitrate Minimum In 4k
60 Mbps
Chroma Sampling In 4k
4:2:0
Bit Depth In 4k
8 Bit
Record Time Limit In 4k
N/A
Overheat Recording Interruptions in 4k
2

4k internal recording capability is decent. There's no recording time limit, which is great, but the camera can overheat and shut down during long recording sessions. Also, while 8-bit 4:2:0 video recording will be fine for most beginner video shooters, it can be a bit limiting if you want to shoot with Log profiles and get more out of your video in post. While the similarly-priced Canon EOS R10 doesn't support Log profiles, it does have an HDR PQ profile that allows for more detailed 10-bit 4:2:2 internal recording.

8.7
4k Video
4k Video Autofocus Performance
Object Tracking In 4k
9.3
Face Tracking In 4k
9.5
Face Detection In 4k
Yes
Eye Detection In 4k
No

Autofocus is excellent in 4k. The camera's tracking works really well. It has little trouble detecting and keeping moving subjects in focus. That said, it doesn't support more precise eye AF in video mode.

7.4
4k Video
4k Video Quality
Low Light Capability In 4k
7.0
Test Scene Extract In 4k
7.8

4k video quality is good. Videos are sharp and detailed, for the most part, though it's only decent in low light. There's some noticeable grain and loss of detail.

4.5
4k Video
4k Video Rolling Shutter Effect
4k Rolling Shutter
9.0°

The Sony a6400 has a slow sensor readout speed, so the rolling shutter effect is pretty bad. It can be quite distracting with quick pans and camera movements.

Full HD Video
9.2
Full HD Video
FHD Video Frame Rate
240 fps In FHD
No
120 fps In FHD
Yes, with a Crop
60 fps In FHD
Yes
30 fps In FHD
Yes
24 fps In FHD
Yes
FHD Crop At Max Available fps
1.14 x

You have more high frame rate options in 1080p, with up to 120 fps recording, though there's a slight crop at 120 fps. That's great for slow-motion video and smooth fast action.

8.3
Full HD Video
FHD Video Internal Recording
Bitrate Maximum In FHD
100 Mbps
Bitrate Minimum In FHD
16 Mbps
Chroma Sampling In FHD
4:2:0
Bit Depth In FHD
8 Bit
Record Time Limit in FHD
N/A

Internal recording is great in 1080p, but just like with 4k, it's limited to 8-bit recording. On the upside, there's no time limit on recording, which is great for longer uninterrupted takes.

8.9
Full HD Video
FHD Video Autofocus Performance
Object Tracking In FHD
9.7
Face Tracking In FHD
9.5
Face Detection In FHD
Yes
Eye Detection In FHD
No

Autofocus is just as good in 1080p. The camera does an excellent job of tracking and keeping moving subjects in focus, even as they move around the frame.

7.3
Full HD Video
FHD Video Quality
Low Light Capability In FHD
7.0
Test Scene Extract In FHD
7.5

1080p video quality is good in proper lighting, though it doesn't perform as well in low light.

6.5
Full HD Video
FHD Video Rolling Shutter Effect
FHD Rolling Shutter
5.3°

Rolling shutter effect is a lot less pronounced in 1080p, which is good. Skewing is less apparent, but it's still present with panning camera movements.

Storage And Connectivity
Storage And Connectivity
Storage
Card 1 Slot
SD Card UHS-I
Card 2 Slot
No 2nd Card Slot

There's just a single SD card slot, and it's on the bottom of the camera, making it a little harder to access when using a tripod.

7.8
Storage And Connectivity
Inputs / Outputs
USB
Micro USB
HDMI
Micro (Type D)
Headphones
No
Microphone
Stereo
Wi-Fi
Yes
Bluetooth
Yes

The inputs are on the left side of the camera. It has a Micro USB port for charging and file transfer, unlike newer models like the Sony ZV-E10, which increasingly have USB-C ports. You also have a Micro HDMI port to connect to an external display, as well as a microphone jack, but no headphone jack.