What is 3D photography?

3D shooting simulates human eyes through two cameras, and takes photos of the left eye and the right eye. At present, the two cameras are arranged in two ways, one is horizontally side by side, and the other is vertically up and down. The distance between the two cameras is generally similar to the pupil of human eyes, 60-65 mm, and the distance between the two cameras can be adjusted according to the close shot or the long shot. It is very important to ensure that the aperture, focal length and brightness between the two cameras are consistent, otherwise the two photos taken will have a lot of uncomfortable feelings at first sight. Of course, many cameras are automatically adjusted by cables now, but it is difficult to ensure that the two are completely consistent. Now there are some studies, such as how much the displacement difference between the two cameras is acceptable and how much the brightness difference is allowable, which is also the standard and main content of 3D measurement in the future, and how much the vertical eye and brightness difference will not be so obvious to people. Another problem is to make sure that the moving object has both left and right eyes when shooting. If a moving object doesn't have a left eye or a right eye when shooting, it will look strange when the objects are recombined and can't be superimposed. Generally speaking, the background of the left and right eyes can be different, but it is necessary to ensure that the moving object falls within the area photographed by the left and right cameras.

People's eyes are 60-65 mm apart, so when looking at things, the image seen by the left eye is different from that seen by the right eye. It is these two images from different angles that will give us a three-dimensional sense after being synthesized in the brain.

The so-called 3D is the left-right displacement caused by parallax, and finally the 3D effect will come out. There are four kinds of parallax: zero parallax, the left eye and the right eye see the same distance; The right eye is in front of the left eye, and the general picture is behind the screen; Negative parallax means that the picture seen by the right eye is on the left of the left eye, and the picture seen by negative parallax should be in front of the screen; Normal eyes can't have scattered vision, so avoid scattered parallax when shooting. Zero parallax is usually a picture of a movie or TV. Which is the screen? Zero vision is almost a movie screen and a TV screen. If you want to use the screen as a reference, the screen can also be used as a reference. The difference in elevation is that the right eye is on the right side of the left eye, its point falls behind the screen, and the effect of the picture is at the back of the screen. The negative parallax picture is in front of the screen defined by zero parallax, the picture seen by the right eye is on the left of the left eye, and the objects are all outside the screen, which will produce a sense of suspension and fly in the visual direction. The scattered parallax will not be scattered by human eyes, and there will be no such picture in real shooting.