QuickGamma Version 4 does not work on any Windows versions prior to Windows 7 and consists of the program QuickGamma.exe, the help file QuickGamma.chm and the printable help file QuickGammaHilfe.pdf. All other files that have been part of previous versions of QuickGamma are not required anymore because QuickGamma Version 4 now utilizes the Windows 7 Display Calibration feature.

Microsoft has introduced a new feature called Windows Display Calibration into Windows 7. Detailed information about how to use the Display Calibration can be found at https://windows.microsoft.com/en-US/windows7/Change-color-management-settings. Besides offering a visual calibration wizard, this feature supplies a LUT loader, which automatically loads the LUT at system start up and whenever else the LUT needs to be reloaded (after waking from Standby or Hibernate for instance). The LUT is a hardware based Look Up Table in the graphics card and provides a means of input value to output value mapping for the RGB pixel values and thus can be used to implement a Monitor Gamma correction.

Apple has been using the LUT since many years for its operating system built in color management. In fact, Apple has registered the private ICC Profile tag video card gamma table (vcgt) with the International Color Consortium (ICC). This tag is used in a dedicated Monitor Profile and holds the gamma values, which are then loaded into the LUT by a loader program.

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

To make things worse, the graphics card manufacturers came up with programs that were installed along with the graphics card driver and allowed the user to play with colors and gamma. These programs were also resetting the graphics card LUT at system startup, which caused a race condition with the LUT loaders of a Hardware based Monitor Calibration Systems. The program that was loading the LUT last won...

Things changed when Windows 7 came along and provided its built in calibration loader, which not only loads the LUT at system start up, but also takes care of Standby and Hibernate.

All it takes to utilize the Windows 7 LUT loader is to install a Monitor Profile with a vcgt tag containing the LUT data and to make this profile the default profile for the respective monitor. Because such a profile is not available by default, the Windows 7 Display Calibration feature is not active by default and must be activated manually.

The visual calibration wizard included in Windows 7 could be used for display calibration, but the images used for the visual calibration are not suited for the job. This is where QuickGamma Version 4 comes into play. QuickGamma Version 4 still contains Norman Koren's excellent gamma images, but now creates a monitor profile with a vcgt tag containing the LUT data. The profile is automatically installed, defined as the default profile for the monitor and the Windows 7 Display Calibration feature is automatically enabled. There is no need for any supporting programs anymore because QuickGamma Version 4 is all it takes to achieve a good visual monitor gamma calibration.