Cubot Rainbow 2 have been launched for more than a month, as the cheapest dual-camera phone, is there any specialty? Here we’ll focus on the phone’s dual-camera on the back.
Cubot Rainbow 2 dual camera are separately 13MP+2MP. 13MP is for the major camera, 2MP is for the secondary camera. 13MP camera is mainly for framing, 2MP camera takes responsibility for zooming and background blur. Here is a introductory video to check:
Then the following shows how the dual camera in Cubot Rainbow 2 works and its principle:
1: About distance
Human eyes are easy to aim at one object, but when people close one eye, they don’t aim this exact object. Dual camera is to simulate the usage of human eyes.
In short, the distance is calculated by the algorithm, the angle of the object with the left/right camera are θ1 and θ2, plus there is a fixed y (that means the distance between the two cameras), it is easy to calculate z (That means the distance from the object to Camera)
it is also easy to calculate when the two camera center distance is too short, the distance to the object will be close. If you want to calculate a long distance, you need to make the distance far from the camera.
1: Optical Zooming
Optical zoom means different camera FOV (viewing angle), so that the two cameras have different views. When the user needs wide-angle photos, he will take 85°angle to have wide-angle effect with the left camera. When the user needs long focus photo, he will take 45°angle with the right camera to telephoto effect.
In order to make the left and right camera shooting overlap objects, the optical zoom dual camera module can not be made so far as the distance of the camera module’s, and the distance between dual camera should be shorter.
Let’s take a look at Cubot Rainbow 2’s sample pictures.
Above photos were taken in Shenzhen Honghu Park http://www.cubot.net/smartphones/rainbow2/