Hardware based Monitor Calibration Systems also use the vcgt tag, which in this case contains the correction data to achievethe monitor calibration. Because Windows did not provide a LUT loader, each calibration program had to provide its own LUT loaderprogram. This was working fine for quite some time until Windows came up with Standby and Hibernation. Unfortunately, the LUT loaderprograms were unable to cope with those Windows features and thus the LUT was reset each time when resuming from Standby orHibernate.