Now, the race for megapixels on smartphones is once again taking place while the sensor size is what needs improvement. Huawei is a good example of upgrading the sensor size instead of increasing the camera resolution.
With the P40 Series, Huawei proudly claims its product has a much larger image sensor size than its competitors. Meanwhile, Sony and Samsung are also gradually moving to grow the sensor size instead of cramming the megapixel count. So why is it so important?
To understand why, we need to understand some basic principles of photography: A large sensor will capture more light than a small one. The more light that is captured, the better the photo will be.
The sensor size determines the amount of light entering the lens.
Simply put, the sensor size will determine the amount of light entering the lens, thereby contributing to the increase in image quality . While resolution plays a role in detail reproduction, the amount of light captured by the sensor affects many factors such as white balance, wide contrast, and sharpness. This is why DSLR cameras with a resolution of only 16MP or 20MP still take better pictures than today’s 108MP smartphones.
Most sensor sizes on phones are usually only 1/2.55 inch (about 1cm). While the new models are equipped with a larger 1/1.7-inch sensor (about 1.49cm). And by comparison, the sensor size on DSLR cameras is very large, about more than 1 inch (equivalent to 2.5cm) – much bigger than on smartphones.
Google Pixel 4 in low-light RAW shooting mode, shutter speed 1/20 second, ISO 800.
The larger the sensor, the more light will be captured, helping the shutter speed, ISO and aperture parameters work better. Although manufacturers can use exposure to achieve this, provided the user has a steady hand and no objects pass by. Otherwise, the image will be blurred and experience the appearance of “ghosts”.
Nikon D3300 in low light RAW shooting mode, shutter speed 1/20 second, ISO 800.
Similarly, wide-aperture lenses help capture more light, but not all manufacturers can meet them. At the same time, large apertures often do not work properly in certain situations.
Another concept we need to know is photosite . These are millions of light-sensitive pixels fitted inside the sensor, arranged in different ways depending on the type. For smartphone image sensors, each pixel is a photosite.
The size of each photosite depends on the resolution and size of the sensor. Same sensor size but the smaller the photosite size, the higher the resolution. In contrast, the resolution stays the same but the larger the photosite, the larger the sensor size.
For small photosites, the acquisition of light information from one pixel may leak to the adjacent pixel, causing noise when shooting in low light. Small sensor sizes and photosites increase noise and reduce dynamic range.
To say that increasing the sensor resolution has no effect is not true. Because in well-lit conditions, a sensor with a super-high resolution like 48, 64 or even 108MP will help photos with better detail.
But in return, in most cases, the camera usually only shoots at low resolution to save space and for faster shooting speed. However, the “cramming” of large resolutions into image sensors by manufacturers is not without purpose. They use a pixel binning algorithm with a high megapixel count to increase light capture.
These sensors, through the pixel binning method, will significantly improve the quality of photos taken in low-light environments, helping to reduce noise and retain colors better. In addition, they also affect shutter speed, ISO, helping to ensure sharp images.
Besides, the large sensor size also helps create a better bokeh effect, similar to professional DSLR cameras. Large sensors can use wide apertures and lenses to create the same bokeh as small sensors, or use the same aperture, smaller lenses for better bokeh.
There are many other factors to create a quality camera system.
Besides the large sensor, there are many other factors that make up a quality camera system. These can be mentioned as “genuine” lenses, powerful image processing chips or well-optimized algorithms, helping to make the most of what hardware has to offer.
In addition, smartphone camera quality is increasingly being driven by advances in processing algorithms and machine learning. They are so powerful that they can beat smartphones equipped with large dots. However, if the two are not well combined, it will still give poor performance. In short, image sensor size is one of the essential components that make smartphone cameras perform better .