If you had to solve a CAPTCHA challenge every time you opened an app on your phone, would you still use that app? That’s how I’ve felt using Sony’s new a6400, where wading through pages of settings and submenus to change vital settings makes an otherwise solid mirrorless camera unreasonably frustrating to use.
The Sony a6400 is a follow-up to the three-year-old a6300, and shares some features with the more expensive a6500. It has a lot of things going for it — like reliably good image quality and a fast hybrid AF system — but those positive traits are buried under a bedrock of convoluted menus and awkward ergonomics. Everything great about this camera is hidden under a menu, overshadowed by caveats, or not present at all.
The main highlights are the Real-time Eye AF and Tracking autofocus features, an updated image processor, and a 180-degree flipping touchscreen. At $899 for the body alone, $999 for the 16–50mm kit lens, or $1299 with an 18–135mm zoom lens, the a6400 has the parts to be the ideal compact powerhouse for any photography enthusiast or vlogger, but it misses on execution.
Using the a6400 these past few weeks, I found out that it’s not quite the game-changing compact mirrorless camera I hoped for, but rather an inoffensive camera with a few good qualities.
A majority of the a6400’s improvements revolve around its updated hybrid autofocus system with more focus points; a total of 425 contrast and 425 phase-detection points, besting the a6300 and a6500’s 169 contrast AF points. It can even hold a candle to Sony’s best full-frame cameras, covering 84 percent of the image area compared to 93 percent on the Alpha A9.
Sony claims a 0.02-second focus acquisition, and I can confirm that the a6400’s autofocus is indeed fast, reacting immediately to a half-press of the shutter button, and correctly identifying its targets the majority of the time.
Number of focus points aside, the real meat of the a6400’s new AF system are Sony’s new Real-time Eye AF and Tracking AF features. Real-time tracking on the a6400 uses Sony’s algorithms and artificial intelligence to recognize subjects and follow them.
Similarly, “Real-time Eye AF” tracks the subject’s eyes and body using AI, and will be updated to support animals later this year. Both features are useful in portrait photography, where a model might move gradually or entirely to a different area of the frame.
Having Real-time Eye AF enabled meant that I simply had to follow my subject with the camera, ensuring the photo was framed to my liking, rather than having to refocus every time and adjust settings if my subject ever moved from position.
But before I can do any of that, I need to actually turn the features on, and they’re not enabled by default. That shouldn’t be so hard, right? After going through fourteen pages of still photography settings (don’t worry, there are another 14 pages just for video) by using only the navigational buttons, I was able to turn on continuous autofocus, eye, and subject tracking throughout the frame. It’s March of 2019 and Sony still refuses to allow their Alpha camera touchscreens to work with the system menus, for reasons unknown and that I can’t understand.
If you’re wondering about image quality: it is solid. That much hasn’t changed in Sony’s Alpha cameras as of late; the a6400 is no exception, and it uses largely the same image sensor as the a6500. Colors pop, objects and subjects appear sharp, ISO can be set from 100–32,000 in native mode, with an expanded ISO of up to 102,400 for dimmer scenarios. Most shots look great in my test scenes, but quality noticeably drops around ISO 12,800, where details appear smudged. The effect is lessened with RAW images compared to JPEGs (RAWs are always better for editing), although that is to be expected because of the additional data available in the file.
Videographers should know that the a6400 isn’t best-suited for video, despite its support for S-Log 2, S-Log 3, and Hybrid Log Gamma (HLG). There are also 4K 24 / 30 fps shooting modes and they look great, but there’s no headphone jack — there’s only a mic port — which is a bummer and essential if you want to check on the audio status of video you’re recording.
Also, the a6400’s SD card slot only supports up to UHS-I speeds, meaning that if you have newer UHS-II SD cards, you’ll only write files as fast as the former, not the latter.
If you were to hold down the shutter button in the 11 fps continuous shooting mode, you’d reach a buffer of 116 frames of JPEG standard or 46 frames of RAW compressed images when writing to the SD card. Having a small buffer didn’t interfere with my shooting, but compared to the a6500’s 300 JPEG and 107 RAW buffer, it’s far less.
Furthermore, the real nail in the coffin for the a6400’s video recording abilities is its lack of in-body image stabilization. That’s the biggest difference between the a6400 and the a6500, and it’s something definitely worth considering when deciding between the two. The lack of in-camera stabilization means you’ll have to rely on your lens and its own stabilization features, which around three dozen Sony lenses do have, fortunately.
Bad rolling shutter is another issue I came across when recording video. Simply panning the camera around will show you a clear 4K image, albeit with jelly-like movement.
The 921k dot resolution display on the a6400 is bright, sharp, and capable of moving 180 degrees to a selfie position, but I have more than a few gripes with it. Besides lacking touch control in the menus, the screen bumps into the viewfinder eyecup when you try to get the full 180-degree position. You can get around this by sliding the eyecup off, but now you’re in a position to lose it.
The hinge design also makes it difficult to use the a6400 for vlogging. Videographers will often place a shotgun microphone on the hot shoe mount of their cameras. Flipping the screen upward would mean that the mic completely blocks the screen, rendering it useless. The solution to this is an articulating screen with a hinge mounted on the side of the camera, but then Sony would need to re-engineer the mic and USB inputs, which are currently on the left side of the camera.
Also, if you do want to use the a6400 primarily for video, I’d recommend setting the programmable “C1” button to be your video recording button. It’s located right next to the shutter button and is much less awkward than the default option, which is placed in the middle of the thumb grip.
A compact camera body is one of the great things about mirrorless cameras taking the spotlight from DSLRs. But the catch is usually that lenses add the weight back on, leaving you with a disproportionately weighted camera, with an even smaller grip. Ultimately, the a6400 will work best with smaller lenses, like the super wide-angle E 10–18mm F4 OSS lens or the compact zoom Vario-Tessar T E 16–70mm F4 ZA OSS lens.
Otherwise, if you pick a heavier attachment like the $2,200 FE 2.8 / 16–35 GM zoom lens I’ve been testing the camera with, you’ll find the a6400’s small grip to be too uncomfortable to leverage the extra weight in glass. Most of the grip side of the camera is occupied by buttons, leaving little space for a user’s thumb and in the case of someone wearing a glove, none at all. For both myself and some of my colleagues on the video team, the a6400’s small grip was just inadequately sized and uncomfortable.
During a shoot, I realized attaching a hot shoe flash and having the zoom lens attached at the same time would prove even more unwieldy, so I stored the larger lens and switched to a Carl Zeiss wide-angle 24mm f/1.8 lens. This is where the a6400 shines, mostly because of the weight reduction. Now it’s possible to hold the camera with one hand and really feel like I have a tool that’s both powerful and wieldable.
On the plus side, the a6400’s body is weather-sealed for moisture and dust — like the a6300 and a6500 before it — but only Sony’s large and expensive full-frame lenses are also weather-sealed, so you should double check your lenses before heading out to shoot in the next downpour.
Battery life is another issue, however. The a6400 uses the same battery as the three-year-old a6300 and so it’s rated at just 360 shots, which I found accurate as it died in the middle of a shoot with some friends. Fortunately, it’s relatively easy to find inexpensive third-party versions of this battery, so I recommend picking up a few spares to keep in your camera bag.
The Sony a6400 is a well-equipped camera with solid image quality and a great price considering its specs. I was impressed with the real-time tracking AF abilities and focus times, but it’s absolutely far from perfect. While some of the a6400’s new features (like real-time tracking) are especially exciting for a camera of this size and price, its flaws like the screen and menu system are nuisances that make it hard to fall in with.
It really feels like Sony has reached the end of the line with what it can do using this camera design. The a6400 has largely the same physical design as the NEX cameras that debuted nearly a decade ago, and it has troubles adapting to larger lenses or new styles of video shooting, such as vlogging.
Sony has done a good job updating the technology inside its APS-C cameras, especially the autofocus system, but now it needs to turn its attention to the body and user interface. If it gets those things right, then it might have the ultimate enthusiast-level camera for photography and video.
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