YI 4K + (Plus)
Image processor: Ambarella H2
Image sensor: Sony IMX377
Display: 2.2 inch LCD
* 330 PPI
* 250 cd / m²
* touch screen
SD card: SDHC / SDXC up to 128 GB
Battery: 1400 mAh
4K HD @ 30
4K Ultra @ 30
2.7K Ultra @ 30
2.7 4: 3 @ 30
1080 Ultra @ 90 / 60 / 30
960 @ 120 / 60
720 240 @
720 Ultra @ 120 / 60
480 240 @
* WiFi, Bluetooth and App
* Loop Recording
* Burst Record
1x YI 4K +
1x Waterproof Case
1x bracket with screw
1x USB-C cable
1x user manual and hint cards
Update (January 2018)
A few days ago, YI Technology rolled out firmware update 1.3.29, which, among other things, eliminates errors in loop recording and the time-lapse mode. As always, you can get the update directly via the app or on the manufacturer's homepage!
Update (November 2017)
A new YI 4K + firmware update is already available for download. The update with version number 1.3.23 is one of the more extensive updates and offers, among other things, sound optimization for “bars” and “concerts”, an improvement in the stability of the gallery, live streaming optimizations and noise reduction for recordings with long exposure times. At the same time, YI Technology has improved the manual IQ parameter settings and the SD memory card compatibility has also been revised.
Update (September 2017)
The Action Cam has now reached firmware version 1.3.11. Among other things, German was added as a selectable language, as well as other languages. In addition, there are numerous optimizations of the existing functions, as well as higher resolutions for time lapse and slow motion recordings can now be selected. Interesting for streamers is the possibility to use the live stream feature from now on.
Update (June 2017)
In the meantime, another update (1.1.7) has been released which, among other things, adds the RAW recording function and voice control and also improves the image quality. The review has been adapted to the YI 4K + Update 1.1.7!
First impression of the YI 4K +
Only at the beginning of last year did the Chinese camera manufacturer "YI Technology" launch the YI 4K (YI 4K review) brought an action cam onto the market that could and can compete with models from well-known manufacturers such as GoPro. At this year's CES 2017, the manufacturer announced a successor to the hugely popular Action Cam. The predecessor model and the successor model look very similar, but a far superior image processor works inside, which enables 4K video recordings at a whopping 60 frames per second. This makes the YI 4K + the world's first action cam with this function and is technically superior even to the GoPro HERO5 Black, which was released a few months ago.
What's in the box
In addition to a hardware upgrade, the scope of delivery was also upgraded. From now on, the scope of delivery also includes an original waterproof housing from YI Technology including bracket. Also included are a 1400 mAh battery, a USB-C cable, and a flood of operating instructions and information cards.
The design of the YI 4K + differs only slightly from the standard model. The camera housing still has dimensions of 65 x 42 x 30 mm and weighs exactly 97g with the inserted battery. If you already own a YI 4K, you can continue to use the accessories with the Plus model. What you can tell the difference between the two cameras is the front, which on the Plus model has a pretty carbon pattern. The exuberant lettering of the standard model has also given way to a simple “4K +”.
The lens equipment of the Action Cam amounts to a 7-layer lens with a 155 ° wide angle and an aperture of F / 2.8. To the left of the lens or lens there is an indicator LED that provides information about the battery level and the recording status. Another indicator LED is located on the top of the housing, which is also integrated into the only physical control button on the camera.
The loudspeaker and one of the two microphones are also placed on the top of the case. Here, too, there is a slight difference to the standard model. The YI 4K had both microphones placed to the left and right of the control button on the top. On the YI 4K Plus, one of the microphones has moved to the edge of the case.
Incidentally, the entire housing frame is now covered with a thin soft-touch surface, which means that the Action Cam is much better held in the waterproof housing, but at the same time it is more difficult to get out. On the back there is a 2.2 inch display with a touchscreen. The connection options are limited to a USB-C socket. The battery compartment, which also contains the micro SD memory card slot, is located on the underside. A ¼ inch tripod thread is attached next to the battery compartment.
A major innovation of the YI 4K + is the use of the USB-C standard as a connection option. In contrast to the Micro-USB socket of the standard model, the USB-C socket is versatile. Among other things, an external microphone can now be connected and the video signal can be tapped directly via USB-C. A corresponding adapter is of course required.
Update (September 2017): The original YI USB-C to 3.5 mm jack adapter is now also available on Amazon (Link to the adapter). Guaranteed to connect any external microphone!
The processing of the Action Cam and the enclosed accessories are not objectionable. The camera leaves a high-quality impression, all control buttons have a good pressure point, there are no unsightly gaps, the battery compartment closes well and the watertight housing included impresses with a good and safe locking mechanism.
Display and touch screen
The back LCD has a diagonal of 2.2 inches in 640 x 360 pixels. Thus a sharp 330 PPI are achieved. The luminance is 250 cd / m². In strong sunshine, the display is only slightly legible. There are also problems with polarized sunglasses, which darken completely when the display is viewed horizontally.
The color rendering of the display is not objectionable. The same applies to the viewing angle stability. Entries made via the small touchscreen are precisely recognized. Inserted in the waterproof housing, the YI 4K + can of course no longer be operated via the touchscreen. Instead, there is the "In Housing Mode" for operation, with which the camera can be completely controlled via the control button on the top.
The YI 4K + is not only the world's first action cam that records at 60 frames per second at 4K resolution, it is also the first action cam with the new Ambarella H2 image processor that enables this recording mode. Manufactured using the 14nm process, the processor is roughly twice as fast as the Ambarella A9SE chip from its predecessor. Videos are recorded with a maximum possible 135 Mbit / s bit rate. The only downer: YI Technology continues to use H.264 for video compression and not the latest H.265 standard! The manufacturer remains true to the 12 megapixel Sony IMX377 image sensor.
Commissioning with obstacles
Starting up an action cam is usually self-explanatory. Insert the battery and SD card and you can start recording. However, it wasn't that easy with the YI 4K +, which is why I have included the sub-item on commissioning in this test report.
My Action Cam was shipped with firmware 1.04. Compatibility problems with SD memory cards were only solved with firmware 1.0.18. When I switched on the Action Cam for the first time and inserted a conventional Samsung Evo SDHC memory card, the user interface of the YI 4K + greeted me with a nice "SD card error". Numerous attempts at formatting were unsuccessful. After all, the memory card was recognized without any problems in my standard YI 4K. Switching to a SanDisk Extreme Pro was also unsuccessful. The "SD card error" remained, regardless of whether it was with the Samsung or SanDisk SD memory card.
So the firmware update 1.0.18 had to be installed. In order to be able to import an update at all, a functioning SD memory card must be inserted. Only a NoName 4GB SD memory card that came with a China tablet was recognized by my YI 4K Plus. After the update was imported, the other two memory cards were also recognized without errors.
YI Technology has largely adopted the user interface of the YI 4K. Only smaller setting options have been added. The start screen or the live image output is surrounded by information on the recording mode, recording time, battery level and whether the microphone and WLAN are active. The recording mode can be changed directly from the start screen. The small gallery icon takes you directly to the gallery, where you can view the recordings on the memory card. As soon as the display is not used for a longer period of time, the display lock is activated automatically and can be deactivated with a swiping movement. This option can be customized within the settings.
Here is an overview of all recording modes and settings options.
Overall, the new YI Action Cam offers 10 recording modes. Here is an overview:
- Photo mode
- Photo Timer (Delayed Recording)
- Burst mode (multiple recording)
- video mode
- Time-Lapse Video (Time Lapse Recording)
- Slow Motion (slow motion recording)
- Time-lapse photo (time-lapse shot with photos)
- Loop Record (If the SD card is full, recordings will be deleted)
- Video and Photo (In addition to a video are stored in photos)
The live video function, through which recordings can be streamed directly on Facebook and YouTube, has not yet been implemented. Even with the YI 4K, this function was only added afterwards! Other promised functions such as voice control or the ability to record RAW image files were implemented shortly after the start of sales with firmware 1.1.7!
The settings menu is divided into two categories. There is a sub-item for the respective “recording mode” and the “general settings”. Here is an overview of the setting options
- Resolution - 4K HD @ 30 4K @ 60 / 48 / 30 / 24 | 4K Ultra @ 30 | 2.7K @ 60 / 48 / 30 / 24 | 2.7K Ultra @ 30 | 2.7 4: 3 @ 30 | 1440 @ 60 / 48 / 30 / 24 | 1080 @ 120 / 60 / 48 / 30 / 24 | 1080 Ultra @ 90 / 60 / 30 | 960 @ 120 / 60 | 720 @ 240 | 720 Ultra @ 120 / 60 | 480 240 @
- Field of View - Near | Middle | Far (depending on the resolution)
- Shutter Speed - Auto | 1 / 240s | 1 / 120s | 1 / 60s | 1 / 30s
- Metering Mode (measurement for exposure) - Average | Center | Spot
- Auto Low Light - Improved shots in low light conditions
- Video Quality - Low | Means | High
- White Balance - Automatic | Native | Artificial light | Daylight | Cloudy
- Color - Flat | YI Color
- ISO Max - Automatic | 400 | 800 | 1600 | 3200 | 6400
- Sharpness - Low | Middle | High
- Exposure - + 2 to -2 in 0.5 steps
- Image Stabilization - On / Off
- Timestamp - Off | Date | Time | Date / time
- Resolution - 12MP | 8MP | 7 MP W | 7 MP M | 5MP
- Shutter speed - car | 2s | 5s | 10s | 20s | 30s
- Metering Mode - Average | Center | commercial
- White Balance - Automatic | Native | Artificial light | Daylight | Cloudy
- Color - Flat | YI Color
- ISO Min - 100 | 200 | 400 | 800
- ISO Max - Auto | 100 | 200 | 400 | 800
- Sharpness - Low | Means | High
- Exposure - + 2 to -2 in 0.5 steps
- Timestamp - Off | Date | Time | Date / time
- Quickview - 0.5 - 5 seconds in 0.5 steps
- File format - JPG | RAW + JPG
- Lens correction ("anti-fisheye effect")
- WiFi - On / Off | SSID and PW | 2.4G / 5G
- SD Card - Available Memory | format
- Standard recording mode
- Bluetooth - to pair a remote
- Display Brightness - High | Middle | Low
- Sounds - Loud | Silently | Out
- Microphone - loud | Quiet | Out
- Sound Effect - Stereo | wind
- Case Mode - Better usability in the case
- External microphone
- Voice control - on / off | voice recording
- Video mode - PAL | NTSC
- Advanced settings - screen lock | Automatic switch-off | Rotate the display | A / V Out USB | Date / time
- Device Info - Firmware | serial number
- Factory settings - Settings | WiFi | Bluetooth
"YI Action" app
If you want to control the YI 4K + remotely, you either need the YI Bluetooth Remote or you simply use a smartphone or tablet. The so-called “YI Action” app is available in the Google PlayStore for Android devices and in the Apple AppStore for iOS devices. A connection between the Action Cam and the app is established via WiFi. The camera is equipped with a dual-band AC WiFi module (802.11 a / b / g / n / ac) and can set up its own WiFi. The app then establishes a connection to this and, among other things, transmits the live image directly to the smartphone or tablet.
In addition to the recording control, all settings can also be made directly via the app. Via the gallery, the recordings stored on the SD memory card can be viewed on the smartphone or tablet, saved and shared on social networks. At the same time, the YI Action App offers its own community platform to exchange ideas within the YI community.
The transmission between the camera and smartphone was consistently stable in the test. Except for a slight delay in the transmission of the live image, the app worked as intended. Access to the SD memory card was also quick and the transmission speeds in both the 2.4G and 5G WLAN networks were not objectionable. In order to keep the Action Cam always up to date, firmware updates can be called up and uploaded directly via the app.
Video quality of the YI 4K +
Due to the combination of the Ambarella H2 image processor and Sony IMX 377 image sensor, the YI 4K + is better equipped in terms of hardware than a GoPro HERO5 Black. For the first time, a resolution of 4000 x 3008 pixels is supported and with a resolution of 3840 x 2160 pixels, the Action Cam is even able to display 60 images per second smoothly.
The video recordings recorded with the YI 4K + impress primarily with a high level of detail and, at the same time, barely perceptible image noise. The color of the Action Cam is very warm. In the YI Color mode in particular, the warmly coordinated hue comes into its own. The camera manages the automatic brightness adjustment quite quickly.
Video recording 4K at 30 pictures-per-second
The video bit rate can reach a maximum of 4 Mbit / s at 135K. With a conventional Samsung SDHC Evo UHS-1, the video bit rate is on 4K HD (4000 x 3008) at an average of 100 Mbit / s and on 4K @ 60 at 120 Mbit / s. But even with a significantly faster SanDisk Extreme PRO memory card, I was able to achieve a maximum of 4 Mbit / s on 105K HD and a maximum of 4 Mbit / s on 60K @ 130. Still a considerable value if you compare it with the YI 4K, which only achieves an average of 4 Mbit / s on 60K. The bit rate of the sound recording is 128 kbit / s.
Video recording 4K at 60 pictures-per-second
The Action Cam is able to stabilize video recordings up to a resolution of 4K @ 30. This is an electronic image stabilization (EIS) that uses an integrated 3-axis gyroscope and a 3-axis acceleration sensor. As is typical for EIS, the image is slightly indented at the edges so that the full recording area is not used.
Image stabilization is a nice feature. However, the EIS of the YI 4K + does not come close to the capabilities of optical image stabilization or stabilization using a gimbal. Slight wobbles are balanced out quite well. In sporting activities, on the other hand, the electronic image stabilization is simply overwhelmed. Sometimes this can lead to unnatural shaking of the image. YI Technology has now got the flickering edges that the EIS of the YI 4K had to struggle with well under control.
Video recording 4K - stabilization vs. No stabilization
In terms of sound quality, GoPro is still ahead of the game. The sound recorded with the YI 4K + is acceptable, but sometimes sounds tinny. If the camera is also in the waterproof housing, the recording volume is greatly reduced. Enclosed you will find two audio recordings, one without and one with a waterproof case.
Sound recording without waterproof housing
Sound recording with waterproof housing
Photo quality of the YI 4K +
Photos can be taken with a maximum resolution of 12 megapixels. Within the general settings, the “Adjust Lens Distortion” function can be used to compensate for the “fish-eye effect” created by the 155 ° wide-angle lens in the software. This option can also be activated for most 4K video recording modes, which is not possible with the YI 4K.
The YI 4K + is suitable for one or two snapshots. Photo recordings convince with a good contrast ratio, an equally high level of detail and a natural color representation. The possibility to record or save images as raw RAW files in the universal DNG format is interesting. At the same time, if you select RAW, the recording is saved simultaneously as JPG (RAW + JPG). The saved DNG files could easily be opened and edited with Adobe's Lightroom. The recordings provided a consistently convincing image quality and offered enough leeway for post-processing.
The so-called Voice Control or voice control is another possibility to control the Action Cam remotely. There are a total of 5 voice commands that allow you to take photos, start and stop a video recording and switch off the camera. By default, the voice commands are recognized in English. For example, when the command “YI Action take photo” is pronounced, a photo is automatically taken. The command “YI Action begin recording” starts a video recording and “YI Action stop recording” stops the recording.
The voice control delivered a high recognition rate in the test. Even with imperfect pronunciation, commands were recognized. The recognition range depends on how loudly the voice command is pronounced. At normal conversation volume, commands were recognized up to about 3 meters. It is also possible to speak your own voice commands. However, converting the English commands into German commands did not work. Even after repeated speaking, only the English voice commands were still recognized!
The YI 4K + uses the same 1400 mAh Li-Po battery as its predecessor. The battery is manufactured by Dongguan Amperex Technology Ltd. , a manufacturer that also produces batteries for DJI, Apple and BMW, among other things. Replacement batteries can easily be bought for this Action Cam. The battery life differs depending on the resolution, how long the display remains active and whether the WLAN is active. The runtimes measured by YI Technology can be seen in the following graphic.
I tried to understand the most important resolutions (4K HD, 4K @ 60, 1080p @ 60 and 720p @ 240) in the battery test. The deviations from the values measured by YI Technology were only minor. With the tested 4K HD resolution (4000 x 3008 @ 30), the average runtime was 90 minutes. On 4K @ 60 I achieved a running time of 64 minutes, on 1080p @ 60 it was 96 minutes and on 720p @ 240 a running time of 92 minutes was achieved. It should be noted that YI Technology determined the values under the best possible conditions.
It takes 1½ hours to fully charge the battery. In comparison, a YI 4K still needed a good 2 ½ hours for a full charge.