tag:blogger.com,1999:blog-1924948806084793655.post4265799665812269127..comments2023-09-26T11:36:56.423-04:00Comments on Machine Vision 4 Users: What to do about lens distortionUnknownnoreply@blogger.comBlogger3125tag:blogger.com,1999:blog-1924948806084793655.post-24863891531937349662013-08-22T11:03:35.687-04:002013-08-22T11:03:35.687-04:00Have you looked at Max Levy?
http://www.maxlevy.c...Have you looked at Max Levy?<br /><br />http://www.maxlevy.com/bulletin1600.cfmAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-1924948806084793655.post-24410619067980009342013-08-22T09:14:08.020-04:002013-08-22T09:14:08.020-04:00The dot grid is fine if the calibration target is ...The dot grid is fine if the calibration target is being viewed at basically 90 degrees. If the dot grid is being viewed at an angle, the center of the image ellipse that gets formed by each dot is no longer the physical center of the circle (which is usually assumed). The checkerboard calibration target instead has intersections of lines, and a line when imaged at an angle to the camera is still a line. If you need to perform 3D calibration use a checkerboard, and if you need just a 2D lens distortion map a dot grid is fine.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1924948806084793655.post-66003867303854906062013-08-16T07:27:33.783-04:002013-08-16T07:27:33.783-04:00I have heard both dots and checker boards are bett...I have heard both dots and checker boards are better than the other from different people. I have found a greater selection of dot patterns commercially available than checker boards and I have not found many sources for either type.<br /><br />Further I have not found a source for checker board patterns that are traceable to a standard. I don't doubt that any of the companies that do manufacture them could provide a checker board grid that is traceable to a standard but it would likely be a custom product.<br /><br />As to a grid that is traceable to a standard, this can be important to those applications where gauging is being performed. It lends credence to the calibration of the camera just like the calibration of any other gauge. It doesn't necessarily make the calibration better, just provides a link to a known standard.Anonymousnoreply@blogger.com