Stereo Vision with close range measurement

Hello, I am working on 3D reconstruction from stereo cameras for close range measurement (30 cm). My camera setting is:

• Two Prosilica GC 1020C 1024 x 768 color cameras with 1/3" sensors
• Two 8mm C-mount lenses

The camera setting looks like this:

It is not perfectly parallel for close range measurement. I followed the guidance and tutorial with the MATLAB stereoCameraCalibrator and fiished the calibration. The calibration looks bad but I tried multiple methods (https://www.mathworks.com/matlabcentral/answers/153348-tips-and-tricks-about-3d-scene-reconstruction) to optimize the calibration process, it didn't work.

However, the reprojection error is not always less than 0.5 pixels (average) and for some cases (I got reprojection error less than 0.5 pixels), the 3D reconstruction falied. It shows a sparse point cloud (looks like noisy data) with the "hand" paired images. I shows that even though the cameras are parallel to the ground (the hands should be on the save level height, but it is not). I am worried if this is the problem with the cameras not for the calibration.

The calibration images are attached, or find in the google link:

Google drive link:

(https://drive.google.com/drive/folders/1RbFlj8AE7AcB6N6qjAofWzA-_B0EbESv?usp=sharing).

I have trided different methods but I am not sure if this is the hardware problems or calibration issues. The 3D point cloud reconstruction is shown in the following:

Rectified images:

Disparity map:

3D point cloud:

Any recommendations would be helpful. Thanks.

[Mert Karakaya]

Were you able to figure out what to do? I have the same issue.