Build 2232 includes some enhancements to the camera calibration distortion image shown by 3DM CalibCam when you double-click on a camera calibration:
Firstly, the distortion image is computed at a resolultion of 4,096 pixels horizontally (with the vertical resolution scaled to match). Previously it was computed at 512 pixels’ resolution and then scaled up. Using a higher resolution means finer details can be seen.
Secondly, any area within the calibration where the effect of the calibration is less than 0.005 pixels is now coloured black. See the S-shaped squiggle in the middle of the image above for an example. As before, moving the mouse over the image allows the precise correction at the given point to be seen in the “Lens Distortion” section at the bottom of the image.
Third, the distortion image now shows the correction from the original (captured) image to the calibrated, “perfect” image. Previously it showed the opposite because that is cheaper to compute. The image now also shows the full correction stored in the calibration; previously it showed a “principal point relative” correction and omitted B1 and B2. As a consequence, calibrations will look slightly different to before and it may also be harder to see the structure of the difference between two calibrations if the principal point offset, B1, or B2 are different between the two. On the other hand, now it will show the complete difference.
Fourth, there is now a grid overlaid with arrows to show the calibration correction direction and size. The arrows are scaled relative to the image size, so that the endpoint of the arrow always shows the pixel in the original image that the pixel at the base of the arrow will be moved to when the calibration is applied. The mouse cursor also shows an arrow but the length is fixed so that the change in direction can still be seen even when the correction is small.
Together, these changes will hopefully make it easier to see exactly what the effect of a particular calibration is and how two different calibrations compare to each other.