Emgu Camera Calibration with micro video lens [closed]

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Hi all,

I am using Emgu 2.4.10 in my C# application. I am using the following camera and lens.

Camera: https://www.ptgrey.com/flea3-13-mp-mo...

Lens: http://www.edmundoptics.com/imaging/i...

In this case I also have extra optical elements. The camera goes through a mirror and then a reflection prism that splits the image. Each split image then goes through its own mirror. Essentially this results in two regions: a left region of interest that corresponds to one of the split images, and a right region of interest that corresponds to the other split image.

In the end I made the whole resolution of the camera 1264 x 512, and each split image has a resolution of 432 x 512.

I performed a separate camera calibration for the left and right region of interest, after the optical elements. I believe theoretically the left and camera calibration should be the same, but there may be slight differences due to alignment issues of the optics and/or camera, which i why I used this approach. However, I seem to be running into a problem. Even after obtaining 25 checkerboard images, I still get a reprojection error of ~1.5 or ~1.6 pixels. Unless I am mistaken, a "good" calibration would have a subpixel reprojection error.

I am wondering if this has to do with the fact that I am using a microvideo lens and my physical detection space is small such that the dimension of a grid in the checkerboard pattern is around 1 mm, and this is not allowing me to get a "good" calibration. Or is there another source of my error?

Thanks in advance.