# 相机

This panel contains all settings of the camera used for filming the movie which is currently being edited in the Clip editor. Different predefined settings can be used here and can be chosen from the panel header. But such settings as distortion coefficients and principal point are not included in the presets and should be filled in even if camera presets are used.

- 传感器宽度
在相机的CCD传感器的宽度。这个值可以在摄像头规格上找到。

- 像素宽高比
是CCD传感器的像素方面。这个值可以在相机规格中找到，但也可以被猜出。例如，您知道素材应该是1920×1080，但图像本身是1280×1080。在这种情况下，像素方面是：1920/1280 = 1.5。

## 镜头

- 焦距
不言自明;这是电影拍摄的焦距。它可以以毫米或像素为单位设置。

- 光心
Is the optical center of the lens used in the camera. In most cases it is equal to the image center, but it can be different in some special cases. Check camera/lens specifications in such cases.

Tip

Optical Center also know as the principal point in photogrammetry.

- 设定中心
See 设置主点为中心.

- 镜头畸变
Mathematical function to convert distorted to undistorted coordinates.

- 多项式
Polynomial radial distortion. Uses three distortion coefficients: K1, K2, and K3.

- 分割
It defines high distortions, which makes this model suitable much better for cameras with fisheye lenses. Use two distortion coefficients: K1, K2.

- Nuke
Distortion model used by the Nuke compositor. Use two distortion coefficients K1, K2.

- 布朗
Brown-Conrady is one of most advanced mathematical lens distortion models. Used to model both radial and tangential distortion. Can use up to four radial distortion coefficients: K1 - K4 and up to two tangential distortion coefficients: P1 and P2.

- 系数
Coefficients are used to compensate for lens distortion when the movie was shot. Currently these values can be tweaked by hand only (there are no calibration tools yet) using tools available in Distortion mode. To do this tweak K1 until the solving is the closest to the known focal length (but also take grid and annotations into account to prevent "impossible" distortion).

- Radial Distortion Coefficients (K1 - K4)
The coefficients in lens distortion models work independent from each other. Positive values will give a barrel distortion while negative values give a pincushion distortion. With a mixture of both negative and positive coefficients you can define more complicated mustache distortions or other complex distortions, that are less common but not rare.

- Tangential Distortion Coefficients (P1, P2)
Works independent and allow to compensate for situations when the sensor is not perpendicular to a group of lens. The optical center (also called principal point) will be shifted (distorted) from the center of the sensor. P1 is used to compensate for sensor rotation in Z (vertical) axes, while P2 is for compensating sensor rotation in X (horizontal) axes. Such distortions can be found in sources from cameras with a sensor stabilization system.