The App shows the message "The calibration sheet cannot be detected."
This message is displayed when the Lens Calibration Sheet can not be detected.
Check the following points or solutions
1. Lens Calibration Sheet
Make sure that the specified lens calibration sheet included with the product is used for calibrating.
If you lose the lens calibration sheet or the sheet is dirty or folded, print a new copy of the sheet.
You can download the lens calibration sheet from this site
Print the sheet in actual size on a plain white paper with your printer.
Make sure that the paper is not dirty, warped, wrinkled or folded before printing.