Wired
Every year the iPhone launches will focus on the improvement of its imaging capabilities, and this year is no exception.
I took a rough count. In the 52-minute iPhone 12 full-series conference, Apple spent about 16 minutes to introduce the progress of its new products in imaging. Especially for the iPhone 12 Pro series, in the 20-minute segment, 13 minutes describe how advanced its photography function is.
Of course, the most curious thing is not the new LiDAR sensor in the iPhone Pro series, because we have already met it on the iPad Pro before. What’s more noteworthy is the larger and “moving” sensor under the main camera lens of the iPhone 12 Pro Max.
The first thing to note is that this eye-catching sensor is only used on the wide-angle camera, which is the main lens. Some friends mistakenly believe that the three lenses of the iPhone 12 Pro Max have larger sensors than the iPhone 12 Pro, but this is not the case. Pro Max’s ultra-wide-angle lens and telephoto lens are equipped with the same sensor as the Pro version.
Apple proudly declared at the press conference, “The size of the main camera of the iPhone 12 Pro Max is 47% larger than that of the iPhone 12 Pro, and the low-light shooting effect is increased by 87%, and the unit pixel size is increased from 1.5 microns. To 1.7 microns”.
If you have not been exposed to photography-related theories before, then these “unclear” data may be difficult to understand. Is this sensor really awesome? What is the use of sensor “displacement”? We need to start with the technical principle of this sensor.
What is a displacement sensor?
Before talking about the technical principle of the displacement sensor, we must first understand what the main parameters of a photo are composed of. Of course, if you already have a certain understanding of photography, you can skip this part.
For consumer-grade or professional-grade cameras, you generally need to manually adjust the ISO (sensitivity), aperture, and shutter speed after turning to manual gear. These three parameters comprehensively determine the lightness, darkness, clearness or blurry of the photo.
When shooting handheld and the light is not so sufficient, the shutter speed will directly affect the clarity of the photo. If you have a slow shutter speed and your hands are shaking while shooting at the same time, you may get a picture like this
This is because your jitter causes a different source of light entering the sensor during the shutter time, so the photo will be blurred or ghosted.
The most straightforward way to solve this problem is to increase the shutter speed so that you can’t keep up with the shutter speed. Which value is safer? In fact, there is no standard answer. This requires a comprehensive judgment based on the camera’s frame, the focal length of the lens and other factors. Generally speaking, it is best not to be less than 1/60 second.
However, the higher the shutter speed, the shorter the time for light to enter the sensor. In low light environments, you have to increase the ISO (sensitivity) and increase the aperture to balance the light and shade of the photo.
Other parameters remain unchanged, the higher the ISO, the brighter the photo. Picture from: photographylife
But the higher the ISO, the worse the purity of the picture, and the more obvious the noise on the picture, which is unbearable for photographers.
Picture from: photographylife
So is there any way to improve these problems? How can you still shoot a clear and clear night with handheld shooting at a lower shutter speed?
Of course, in order to solve the above problems, camera manufacturers have developed anti-shake technology.
The common anti-shake technology on the camera is mainly divided into two kinds, one is lens anti-shake, and the other is body anti-shake, which is the “displacement sensor” anti-shake in Apple’s mouth.
Picture from: xitek.com
The world’s first lens anti-shake system for civilian cameras was developed by Canon. It was first used on Canon EF 75-300mm F4-5.6 IS USM lens in 1993. This is the first application of optical anti-shake system in civilian cameras. .
Lens image stabilization
The development history of body anti-shake is relatively short, and it has not yet been popularized in low-end cameras.
Body anti-shake is to offset the vibration caused by hand shake or the machine through the movement of the photosensitive element, thereby achieving optical anti-shake. Cameras of high-end models such as Sony, Canon, and Olympus can already achieve “five-axis anti-shake.” This is also the anti-shake principle of the new sensor of iPhone 12 Pro Max.
Through lens anti-shake or body anti-shake technology, we can easily take clear pictures in hand. Even when the shutter speed is reduced to 1/30, 1/15 or slower, pictures without ghosting can be taken.
The first application of sensor displacement technology on mobile phones
Since body anti-shake is not a new technology, what’s worth paying attention to with this sensor exclusive to iPhone 12 Pro Max?
It should be noted that although this technology is quite mature, it has been used in cameras before. Compared with mobile phones, the internal space of the camera is much wider. It is not an easy task to realize the optical image stabilization of the sensor in the small space of the mobile phone.
So from this perspective, the iPhone 12 Pro Max is the first mobile phone with sensor displacement anti-shake.
Perhaps seeing this, some people will doubt: Isn’t the “Micro-Pan” technology of the vivo X50 series phones earlier than the iPhone 12 Pro Max?
In fact, the technical principles of the two are in two directions. In vivo, the lens group and the sensor are connected as a whole and placed in a double-ball suspension, so that the lens group and the sensor can move together to achieve optical anti-shake.
vivo micro-head technology
The lens group and sensor of the iPhone 12 Pro Max are still separate. Unlike other models, the lens anti-shake solution for the main camera has been changed to a sensor anti-shake solution. Just like the technology used in the above-mentioned SLR, the optical image stabilization effect is achieved through sensor displacement.
Compared with lens anti-shake, Apple said that the sensor displacement anti-shake is more advanced and can bring a better anti-shake experience.
According to Apple, this sensor can accurately control the dynamics of the X-axis and Y-axis, eliminating low-frequency and high-frequency interference, such as hand shake or car vibration. Through the entire optical image stabilization system, the iPhone 12 Pro Max can obtain a stable exposure time of up to 2 seconds under low-light conditions, which is equivalent to increasing the first-level aperture exposure.
In fact, the benefits of the anti-shake upgrade can be more intuitively reflected in video shooting. With Dolby Vision and 10-bit HDR video shooting capabilities, iPhone 12 Pro Max will become one of the strongest camera phones in the short video era.
The largest sensor in iPhone history
The point of concern for this sensor is not only the displacement-type anti-shake technology, but also its larger size.
As mentioned above, the sensor size of the iPhone 12 Pro Max’s main camera is 47% larger than that of the iPhone 12 Pro, which is almost half the size, becoming Apple’s largest image sensor so far.
In the photography circle, we often hear a sentence that is “crushing people to death”. It means that the larger the sensor size, the larger the photosensitive area, the more light it can capture, the better the photosensitive performance, and the higher the signal-to-noise ratio. Simply put, the better the imaging effect.
In the impression of many friends, the higher the pixels, the better the picture quality. In fact, this is a one-sided perception. In fact, increasing the size of the sensor is more important for improving the picture quality than increasing the pixel. The effect of a 1/1.8-inch 8-megapixel camera is generally better than a 1/2.7-inch 12-megapixel camera (the photosensitive area of the latter is only 55% of the former).
Mobile phone cameras of various sizes. Picture from: alibaba
At present, we do not know the specific size of the iPhone 12 Pro Max main camera sensor. For reference, the size of the iPhone 11 Pro main camera sensor is 1/2.55 inches.
A larger sensor means more light. This is as large as the room area, but the windows are larger, so the light in the room will be better.
Apple said that this enlarged sensor has enabled the iPhone 12 Pro Max to “improve 87% in low-light shooting.” This data proves that the new sensor’s shooting performance in low light environments will be stronger than that of the iPhone 12 Pro, and the improvement is more obvious.
Apple official sample
Even if the sensor size is increased, 12 million pixels are still selected for the main camera of the iPhone 12 Pro Max. The benefit of this is that the unit pixel size of the photo has increased from 1.5 microns to 1.7 microns.
It’s like the room has grown, the same number of balloons can be blown bigger. The larger the unit pixel, the more information will be carried, so that the latitude and purity (noise control) of the photo will be better.
Apple official sample
The reason why Apple insists on 12 million pixels is actually to balance photography and video. For example, Sony’s full-frame mirrorless A7S series, in order to highlight its video shooting capabilities, always adhere to 12 million pixels.
This is because for 4K video recording, a 12-megapixel sensor is the optimal solution. After this pixel is cropped to 16:9, it happens to be the 4K resolution rounded up, making the most of the effective CMOS pixels to optimize the video quality without putting too much burden on the processor.
To be honest, this time the iPhone 12 Pro Max shines the most on this displacement sensor. And I have reason to believe that sensor displacement technology will soon be popularized on next year’s flagship machines. Because this technology can not only bring better anti-shake effect, but also reduce the difficulty of lens module design, and achieve stronger optical quality within the same thickness.
At present, iPhone 12 Pro Max may be one of the best choices for professional photographers and videographers. Unfortunately, it continues the weight of the previous generation. The 226 grams makes it impossible for patients with tenosynovitis to love it. It may make photographers who like small-screen mobile phones tangled.
This article from the micro-channel public number: Love Fan children (ID: ifanr) , Author: Wang Helong, title figure from: CFP