What is Focal Length?
Focal length is one of the most important parameters in 3D visualization. It defines the distance between the camera and the subject, and has a significant impact on the final image. A shorter focal length will result in a wider field of view, while a longer focal length will give a narrower field of view.
The choice of focal length depends on the desired effect. For example, if you want to create a sense of depth, you would choose a long focal length. On the other hand, if you want to capture a wide area, you would choose a short focal length.