# Triangulate Chessboard gives weird results

Hi all,

So I'm trying to create a projection in 3D with use of stereo camera with use of Python.

I found the intrinsic camera calibration parameters, which seem good. Then I find the chessboard corners on both images with :

_, C1 = cv2.findChessboardCorners(img1, (6, 9), None).

I undistort the found corners with:

C1Norm = cv2.undistortPoints(C1, K1, D1)

And use those to find the essential matrix with:

E, mask = cv2.findEssentialMat(C1Norm, C2Norm, focal=1.00, pp=(0., 0.), method=cv2.RANSAC, prob=0.999).

And at last I find the rotation and translation between the cameras with:

M, R, t, mask = cv2.recoverPose(E, C1Norm, C2Norm).

Now with use of that I find the projection matrix of both cameras;

P1 = K1 * [I3 | 0] and P2 = K2 * [R | t] where K1 and K2 are the intrinsic camera parameters and I is an 3x3 identity matrix.

Last step now should be to triangulate. I use 4D = triangulatePoints(P1, P2, C1Trans, C2Trans) which gives me the 4D coordinates.

However, when I plot this, my chessboard is all crooked and wrong. Has anyone any idea where something might go wrong?

Also, I know the dimensions of the chessboard, any idea how I can turn the homogeneous coordinates of the chessboard corners to cm?

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