Hi Grant,
thanks for your answer,i use the same traker 4c device for 32 inch screen and previously used is 27 inch in the same place and with the same laptop ,the accuracy of Y position would be improved to 10 millimeters divation,while Z position divation has not been imporved,
and if i change another user(without glasses),after running the user calibration,the result has not been changed.
what confused me is that why the result is very different between 32 inch screen and 27 inch screen with the same tracker 4c after calibration.and 32 inch screen seems better than 27 inch.
thanks.