we're using the camera_pose_calibration package and try to calibrate multiple camera's with it. We followed the instructions at http://www.ros.org/wiki/camera_pose_calibration - which went well. The camera nodes are started, the images appear properly in the calibration gui, but we have trouble detecting the checkerboard pattern. Although the pattern appears, clearly visible and sharp, in both images, no corners are detected (see screenshot attached C:\fakepath\Screenshot-13.png). We tried this with 2 kinect camera's at first, and with 2 prosilica Gige camera's afterwards (we thought image quality might matter here, but it's no different). We tested with both mono and color images. Any suggestions / comments on how to check what is going wrong here?