Pixel binning in smartphone cameras: All you need to know

From the past couple of years, you must have heard a term called pixel binning when companies talk about smartphone cameras. While the term might not boost your excitement, but is a technology embedded in camera and powers most of the smartphone camera now. So, what exactly is pixel binning?

Before, we dive deep into the technology lets first understand what the pixels represent in cameras. Pixels are physical elements in the camera sensor that capture light when you shoot images and is measures in microns and is generally referred to as pixel size. Some of the smartphone such as iPhone Xs Max, Galaxy S10 have large pixel size 1.4 microns – anything below one micron is considered small. And to have a better photography experience, a smartphone should have a large pixel size as can capture more light which means the camera can click great images in low-light settings too such as pubs or cafes. And since the design of smartphone is not as big as DSLRs, companies use the pixel-binning approach to enhance the photography experience.

Pixel Binning

To put it simply, pixel binning approach combines data from four adjacent pixels to form a high-resolution image. For instance, let’s say a camera sensor has pixel size of 0.9 micron pixels, and with pixel binning technology, the camera sensor can produce results equivalent to 1.8 micron pixels.

Let’s also take an example of an 48MP image sensor. If the pixel binning approach is used, the actual image shot is only 12MP from one pixel and then four pixels each of 12MP are then combined to create an 48MP shot. The main disadvantage of this approach is that resolution is divided into four. Thus, a 16MP binned-shot is only 4MP.

Now since most of the smartphones now use a quad bayer filter on camera sensors which captures an image with RGB colours, pixel binning has been made possible on smartphones. A standard bayer filter is made up of 50 per cent green filters, 25 per cent red filters and 25 per cent blue filters. The bayer filter then makes clusters of four, and later uses software-based array conversion processing to enable pixel binning. The cluster arrangement ensures camera allows more light to let in for an improved result.

So, how to know if a camera uses pixel binning approach. Well, if you encounter a smartphone that has 32MP or 48MP or 40MP camera configuration, it’s almost sure that it uses pixel binning approach.

A few of the devices that use pixel binning technique include the Xiaomi Redmi Note 7 series, Xiaomi Mi 9, Honor View 20, Huawei Nova 4, Vivo V15 Pro, etc.