Dual camera smartphones, how they work and what they are for

Dual rear cameras allow smartphones to capture more details and take perfect pictures

Among the features that users look for nowadays in a smartphone is often the dual lens rear camera, commonly called dual camera. In the beginning they were only found in top of the range devices while now even in mid-range devices it is easy to encounter them. But what's the point of having two cameras?

Let's start from the base, a dual camera phone is a device that integrates in its back two sensors. The main purpose of this solution is to make the images taken by the smartphone as detailed as possible. The goal is to simulate human binocular vision and thus create three-dimensional images. Not all smartphones use dual lenses in the same way, but in almost all of them there is a main camera that does most of the work while the second one is used to emphasize details or objects in the foreground.

What's the point of a dual camera

One of the first companies to use a dual rear camera was Huawei. The Chinese company adopts a fairly unique solution: one sensor is dedicated exclusively to black and white photos, while the other is dedicated to color photos. Details from the monochrome sensor are used to improve images taken with the RGB sensor as well. So far, there are essentially four advantages that a dual camera has over a single one: getting a greater depth of field, speeding up focusing, reviewing the focus of photos after shooting, and improving the quality and details of images.

History of the dual camera

The dual camera has been a relatively recent success but manufacturers have been working on it for at least three years. For example, HTC M8 and Honor 6 Plus allowed users to vary the aperture after shooting. A choice that today has been taken up by Xiaomi Redmi Pro and Honor 8. Apple, on the other hand, mounts a dual camera on the iPhone 7 Plus and allows you to use a 2X optical zoom and capture images with bokeh effect. This is the perfect effect for taking portrait photos. Oppo a few months ago promised the release of a dual lens with 5X optical zoom but as of now there is no news about it. LG G5 and LG G6, on the other hand, use the second camera to widen the angle of view, to create a sort of wide-angle lens.