Charts

calibration charts the 3 charts below are the main charts used for all calibration done inside ncam reality, if printing your own versions of these charts it is vital that they are printed to the correct size and not scaled in any way 70mm april tag mosaic preferred can be used for spherical lens calibration, witness to main relation, stereo calibration download link a3 1 "dots" can be used for spherical lens calibration, witness to main relation download link 3cm checkboard can be used for anamorphic lens calibration download link fiducial anchors these patterns are referred to as "fiducial anchors" or sometimes instant recovery they are primarily used as a way for the ncam system to recover tracking when starting the system they can also be used as part of the witness to main " liveupdate " process if using these charts for tracking recovery, they should be placed in a permanent location in your tracking environment and they should be printed large enough to be detected by the ncam camera bar take care to ensure the pattern is not bent or warped when applying it in your environment repeating anchors only use a specific fiducial anchor once per tracking environment, multiple can be used but choose a different pattern if placing more than one download link download link download link download link download link registration object this chart is referred to as the registration object and is used as a method for setting the zero point of the tracking it is used as part of some of the setup wizards in the webui, and can also be used in the full ui it can not be used as a "fiducial anchor" if printing this chart yourself ensure that it is printed at a 1 1 scale the ncam system expects it to be a certain size and if the chart is printed smaller/larger than expected then this will cause issues with how it is detected download link object tracking the charts below can be tracked and their position sent to unreal by the ncam system visit the object tracking page for more information download link download link tips for printing charts if printing your own charts there are a couple of important points to be aware of all charts must be absolutely flat, printing onto paper is fine, but the print must then be carefully stuck to a firm board ensure there are no deformations or warping in the pattern even slight irregularities can cause quite noticeable side effects, particularly when using the charts for lens calibration other than the fiducial anchor charts, all other patterns must be printed to the correct scale if printing at home, ensure that your printer is not applying any scaling or squeezing of the chart pattern as part of the printing process