After the separation of the two brands of Xiaomi and Redmi, Xiaomi's main products are positioned as mid-to-high-end, but the core of the main cost performance has not changed. Xiaomi Mi 9 belongs to the regular upgrade of the Xiaomi digital series, with a minimum price of 2999 yuan. As can be seen from the configuration table, most of the cost is spent on more core hardware, such as Snapdragon 855 and IMX586.
 
Now there is not much room for the cost of hardware to go down, if Xiaomi wants to go to the high-end, it will be difficult to coordinate price and performance, after all, you get what you pay for. After the press conference, Lei Jun also said that Xiaomi Mi 9 is likely to be Xiaomi's last flagship machine below 3000 yuan.
 
At the press conference, Lei Jun spent a long time explaining the exterior design, especially the full curved surface and holographic color process on the back of the mobile phone. I have to say that after the Xiaomi Mi 6, the exterior design of the Xiaomi Mi 9 has returned to the level it should be. Hyperboloid is not a new technology, but on the Xiaomi Mi 9, it does have a noticeable effect on the improvement of look and feel. Xiaomi Mi 9The thickness of the fuselage is only 7.61mm, plus the full-curved back cover, the thickness can be further reduced visually, and the appearance is about 5mm, which also causes the lens module to protrude a lot from the back of the fuselage, and it will be warped when placed on the desktop, and it takes a very thick phone case to smooth out this gap.
 
The holographic color on the back sounds lofty, but in fact it is nano holographic pattern and nano double-layer coating technology, and the main technical difficulty lies in how to adjust the color that the designer wants, which will consume a lot of time and cost in the proofing stage. The first model has a holographic color blue and holographic color purple, but this purple is actually pink, and there is also a space gray (gray black), and a transparent version will be launched in the future, and the back element decorative plate is carved out of 0.3mm aluminum sheet, which cannot be simply understood as a "sticker".
 
Xiaomi Mi 9The back uses the sixth generation Corning Gorilla Glass, the rear fingerprint is canceled, and the vertical dual camera is upgraded to the vertical triple camera, and there is a circle of color decorations around the top camera, which is not amazing, but it is definitely much better than the Xiaomi Mi 8. After getting started, Xiaomi Mi 9 fits very well in the palm of your hand, but the back is relatively slippery, and the risk of falling is greater, so it is still recommended to use a phone case.
 
The front uses a 2340×1080 Samsung AMOLED waterdrop screen, which is a normal operation at this price. Compared with the big notch of Xiaomi Mi 8, the waterdrop screen of Xiaomi Mi 9 occupies less area, and the screen-to-body ratio has also been improved, with the officially announced screen-to-body ratio reaching 90.7%. The maximum brightness of the screen is 620nits,The color performance belongs to the normal level of the Samsung A screen,The color accuracy has not been significantly overturned,It's about the same as Mi8。 As for the anti-blue light certification, the main credit is Samsung's A screen, because the screen has taken the German Rheinland anti-blue light certification, so the mobile phones with this screen are considered to have anti-blue light certification, and the PWM low-frequency dimming problem of the OLED screen still exists.
 
Xiaomi Mi 9 changed from back fingerprint unlocking to under-display fingerprint unlocking, using the fifth-generation under-screen fingerprint unlocking scheme, that is, placing a short-throw camera under the screen to detect fingerprint unlocking. The unlocking speed is very close to physical fingerprint unlocking, but there are still shortcomings, such as wet hands can not be unlocked, the unlocking area is not large enough, but the cost and time are limited, there is no 3D structured light, and half-screen fingerprint unlocking also has to wait for other manufacturers' products.
 
In terms of processor, Xiaomi is the first "in stock" Snapdragon 855 mobile phone, in the Android camp, Snapdragon 855 relies on the excellent performance of Adreno640 to stabilize the Mali-G76MP10 of Kirin 980. In the Honor of Kings HD mode, the 855's frame rate has been stable above 58 fps, and in the benchmark test, the gap between the 855 and the Kirin 980 is quite large.
 
As for the Mali-G76MP12 of the Samsung Exynos 9820, the Snapdragon 855 can score 55 in most of the Benchmark projects, and in some projects such as GFX3.1 Manhattan and Aztek Vulkan, the 855 has opened a big gap. As for CPU performance, the 9820's Mongoose M4 does beat the 855 in single-core scores, but in most PCMark Work 2.0 projects, the 855 has an advantage over the 9820.
 
In terms of photography, Xiaomi Mi 9 adopts a rear triple camera scheme, from top to bottom, IMX481, wide-angle macro, 16 million pixels; IMX586, main camera, 48 million pixels, support 4-in-1 output; Samsung S5K3M5, telephoto, 12 million pixels. The Xiaomi Mi 9 ranks third in DxO, with the Huawei Mate 20 Pro, Huawei P20 Pro, and Samsung S10 Plus scoring higher than it.
 
With the IMX586 blessing, the Xiaomi Mi 9 performs as well as it should, especially in daytime imaging, with generally accurate white balance, well-controlled noise, and fast and accurate autofocus, but the main drawback is the lack of dark detail in high-contrast scenes, which is understandably high for DxO. However, the DxO doesn't have a night test session, which is a relatively obvious weakness of the Xiaomi Mi 9. Compared with the Honor V20 that also uses IMX586, Xiaomi Mi 9 Even after turning on Super Night Scene, there will be general highlight suppression in high-contrast scenes at night, and the problem of insufficient retention of dark details will occur, and there will even be a lot of noise in low-brightness and high-contrast scenes, which will slightly overturn.
 
IMX586Although it supports480000000 pixels,But you need Xiaomi9In the professional mode to use the true4800000000000 pixels,The imaging speed is slow,And there will always be a small part of the color shift after magnification,As for the 480000000 in the automatic mode,Mainly through 120000000 pixel interpolation,The resolution has indeed improved,But after all, it is interpolation,If you look closely, it will still be exposed。
 
In terms of system,Xiaomi Mi9Equipped with MIUI 10 based on Android Pie,And the already very easy to use"Full screen gesture",Xiaomi has also improved,On the basis of sliding inward at the left and right ends of the screen to"Return"On the basis of not letting go of your finger and sliding to the middle of the screen,It will trigger the operation of switching between the two applications,Make"Full screen gesture"Better to use。 Although MIUI's localization, functionality and humanization are difficult for many manufacturers to achieve, the built-in advertising in its system has also been criticized by many users, and if you want to maximize the removal of ads, you can only buy Xiaomi members.
 
In terms of charging battery life,Xiaomi Mi 9There are bright spots,There are also shortcomings,The disadvantage is that the battery capacity is only3300mAh,It is quite small in the flagship,But it does not show obvious shortcomings in battery life,It shows that the battery management scheme is still relatively scientific。 The highlight is that Xiaomi supports 27W fast charging and 20W wireless charging, which is quite enough for a 3300mAh battery, from 5% to 100%, with wired charging taking only 70 minutes and 90 minutes using wireless charging. However, Xiaomi's 27W fast charging and 20W wireless charging can only reach the maximum power of the Xiaomi Mi 9.