extrinsic result seems not ok--after run roslaunch camera_lidar_calibration getExt1.launch

[ajiang17]

Hi,
I‘m using camera_lidar_calibration getExt1.launch to get lidar to camera extrinsics . I'm using 10 pairs of pics and pcds , total 40points.
Logs are pasted below. Although CONVERGENCE, the project error is much bigger than threshhold.
Please Help me, what is wrong ?

---------------Logs:
iter cost cost_change |gradient| |step| tr_ratio tr_radius ls_iter iter_time total_time
0 3.263738e+05 0.00e+00 6.46e+05 0.00e+00 0.00e+00 1.00e+04 0 7.46e-03 5.42e-02
1 1.841992e+05 1.42e+05 1.67e+05 1.47e+00 9.54e-01 3.00e+04 1 1.46e-02 6.89e-02
2 1.768749e+05 7.32e+03 5.10e+03 2.50e-01 1.00e+00 9.00e+04 1 4.70e-05 6.90e-02
3 1.768657e+05 9.27e+00 9.36e+00 1.09e-02 1.00e+00 2.70e+05 1 7.41e-05 6.91e-02
Ceres Solver Report: Iterations: 4, Initial cost: 3.263738e+05, Final cost: 1.768657e+05, Termination: CONVERGENCE
-0.721294 -0.692535 0.0122162
-0.00404571 -0.0134298 -0.999907
0.692631 -0.721267 0.0068757
0.264165
-0.00771116
-1.74526
Use the extrinsic result to reproject the data
Data 0 has a error bigger than the threshold
xyz are 5.83209 -6.24977 0.447996
ErrorU is 13.851 errorV is 9.07203

.......

---

Data 36 has a error bigger than the threshold
xyz are 4.55385 -4.30335 0.334322
ErrorU is 27.3254 errorV is 14.5054

---

Data 38 has a error bigger than the threshold
xyz are 4.07123 -4.82789 -0.658529
ErrorU is 19.669 errorV is 11.8685

---

Data 39 has a error bigger than the threshold
xyz are 4.55385 -4.30335 -0.658529
ErrorU is 20.7527 errorV is 20.7066

---

u average error is: 27.4879
v average error is: 34.0989

The reprojection error bigger than the threshold, extrinsic result seems not ok

[chychiang]

Getting the same error with the provided sample data.

u average error is: 13.7469
v average error is: 14.7411

[springslx]

@ajiang17 @chychiang Hi, I get the same errord with the provided sample data. Did you solve the problem?
`
intrin:
952.339 0 793.155
0 949.096 255.112
0 0 1

Use the extrinsic result to reproject the data
Data 10 has a error bigger than the threshold
xyz are 4.773 -1.285 -0.381
ErrorU is 11.1892 errorV is 6.6026

---

Data 11 has a error bigger than the threshold
xyz are 4.75 -1.285 1.139
ErrorU is 3.69858 errorV is 11.7171

---

Data 19 has a error bigger than the threshold
xyz are 4.731 0.333 1.054
ErrorU is 0.107852 errorV is 12.0369

---

Data 27 has a error bigger than the threshold
xyz are 4.495 0.06 0.997
ErrorU is 1.48431 errorV is 20.8934

---

Data 28 has a error bigger than the threshold
xyz are 4.296 0.43 0.966
ErrorU is 4.52526 errorV is 24.4341

---

Data 29 has a error bigger than the threshold
xyz are 4.292 0.437 -0.369
ErrorU is 4.78589 errorV is 8.26999

---

Data 31 has a error bigger than the threshold
xyz are 4.383 -0.559 0.991
ErrorU is 0.533192 errorV is 18.0158

---

u average error is: 3.03319
v average error is: 6.02012`

[springslx]