When shooting grids, the camera should be placed an Angle that is not perpendicular to the grid pattern, so the captured image contains two definite vanishing points.
拍摄时网格，相机应该放在一个角，不是垂直于网格模式，所以捕获的图像包含两个明确的消失点。
2
An easy and practical method of measuring Angle is presented, which is measuring the Angle of revolving turntable by solving vanishing point.