What is the significance of the lateral movement of the hand roll in photography techniques?

The push-pull technology of lens is a set of technologies that are technically opposite, and one of them can often be used to realize the other in nonlinear editing. Pushing the lens is equivalent to walking directly along the straight line of the object to see the object, while pulling the lens means that the camera keeps leaving the object. Of course, both of these technologies can be realized through a zoom lens. The role of push lens in shooting focuses on highlighting important Russian figures or objects in later films, which is the most common role of push lens. It can make the audience's line of sight gradually close to the subject, and gradually guide the audience's observation from the whole to the part. In the process of pushing the ground, the content contained in the picture gradually decreases, that is to say, the movement of the lens abandons the superfluous things in the picture, highlights the key points and leads the audience's attention to a certain part. Using zoom lens can also achieve this effect, that is, gradually moving from short focal length to long focal length, so that the audience can see the subtle parts of the object and highlight the key to express the content. Pushing the lens can also show a huge space. Pulling a lens is just the opposite of pushing it. This means that the camera keeps moving away from the subject, and you can also shoot with a zoom lens (gradually adjust from a long focal length to a short focal length). It has two functions, one is to show the position of the protagonist or scenery in the environment. The lens moves backward and gradually expands the field of vision, which can reflect the relationship between the part and the whole in the same lens. Second, it is also necessary for the connection between shots. For example, the former is a close-up shot of one scene and the latter is a shot of another scene, so it is much more natural for the two shots to connect like this. The push-pull effect of lens is different from zoom. For example, in the technique of pushing the lens, the method of using zoom lens is equivalent to magnifying a part of the original subject. The effect on the screen is that the relative position of the scene remains unchanged, and the scene remains unchanged, but the original picture is enlarged. It is more suitable to use zoom lens to achieve this lens effect when the main body of the shooting scene has not changed and it is required to approach the object at any speed without continuous jitter. Moving the lens to push the lens is equivalent to observing close to the subject. The effect in the picture is that the objects in the scene move backwards and the size of the scene changes. This is very effective when shooting narrow corridors or indoor scenery. There is a clear difference between moving the camera and using the zoom lens to achieve the push-pull effect of the lens, so we need to have a clear understanding of the shooting concept and cannot simply replace the two.