How multiple cameras work on smartphones have always been a question on the minds of most people and 2019 is the year of multiple cameras and many if not all smartphone brands have released phones with multiple cameras. You’ve probably seen the Nokia 9 Pureview with 5 cameras and the Huawei P30 Pro that comes with 4 cameras (40MP + 20MP +12MP +TOF Camera) and 50x optical zoom.

Huawei P30 Pro
Nokia 9 Pureview

These two devices come with crazy specifications but I won’t go into that right now, maybe in another post.

However, have you ever tried covering the main camera of your device with a dual camera?

If you haven’t, try doing that right now.

You’ll notice you are actually blocking the whole camera. That leaves the question – What do the secondary cameras do and how do they work.

How Multiple Cameras Work

Now I want you to understand this. Most OEMs have other uses of their secondary camera other than the ones I’m going to mention below. These are just the basic functions of the secondary camera.

The secondary camera improves the overall clarity of the image with the help of a “Monochrome” feature. The secondary camera only records the black and white version of the image. With the help of the Monochrome sensor, the primary camera measures how much light is coming from the point of focus.

Previously (with the exception of the Google Pixel 3), the primary camera in smartphones normally handled the measurement so there was a very high possibility of losing some detail while measuring light intensity since it would still need to work on the color filtering.

So this extra burden is handled by the second camera which takes care of that area. Combining the monochrome image which has detailed information about the light and sharpness with the colored image that was captured by the primary camera will produce a rich and detailed image.

In some phones, the secondary camera acts as the zoom lens. Huawei uses their cameras on the P30 Pro a bit differently but going into the entire details might end up making this post a bit lengthy and a bit boring for people who aren’t hardcore techies so I’d try to keep this balanced. However, if you’d like to see that in another post do let me know in the comments.

So that’s basically how multiple cameras work on smartphones.