Baier photography

We know that under normal circumstances, if the camera is shooting in motion, the background of the picture will also move and shift accordingly. However, the colors of green screen and blue screen are monotonous and consistent, and there is no depth relationship, which often cannot provide accurate camera motion information for later synthesis. Therefore, it is necessary to add some marks on the screen. By tracking these key points, post-producers can find the information of the camera, thus adjusting the movement relationship between the protagonist and the background. Setting the tracking point is generally to stick some equidistant or equal lines or points on the green screen and the blue screen. If it is detailed enough, these marks can be made different.

At present, the application of green screen is more than that of blue screen, because most cameras have twice as many green pixels as red and blue in CMOS Bayer image array, with the strongest signal, the least noise and the most brightness information. Blue noise is at most the darkest, so blue screen is generally not recommended.