Adobe Gamma control panel The ideal tool for monitor calibration is the Adobe Gamma software, which comes as part of Adobe Photoshop from version 5.0 onwards; it is not supplied as part of Photoshop Elements. This software has the advantage that it is available to both Windows PC and Mac users, and is automatically installed in the Control Panels folder or directory by default both on the Mac and in Windows, when installing Photoshop. As an alternative your graphics card should offer basic adjustments for the Gamma Controls, although the accuracy will depend on the actual monitor itself. If you are using the Adobe software we would suggest that you do not make any adjustments to the graphics card settings. Step one – Basic Monitor Calibration Before starting calibration, turn the monitor on and leave for at least thirty minutes so that everything can stabilise before adjustments are made. It is also recommended that you do this prior to any on screen editing to ensure consistency. Windows users can find Adobe Gamma in the Control Panel [Start>Settings>Control Panel>Adobe Gamma]. Mac users will find it at [Apple Menu>Control Panels>Adobe Gamma]. Open the Adobe gamma control panel, and choose the Step by Step Wizard for a first calibration:
To provide a starting point for your calibration click on ‘Load’ and from the list we would recommend that you select the ‘srgb color space profile’ and then click on ‘Next’.
Now adjust the monitor's contrast control to maximum, and set the brightness control so that you can just discern a difference between the two centre squares. Tape over the monitor controls so they can't be moved accidentally. You have now set the dark point of your monitor:
Now enter the phosphor setting best suited to your particular monitor if you know it - the menu gives a choice of pre-defined phosphors, Trinitron for example. For more accuracy, your monitor user manual should state the x-y r, g and b numeric values – otherwise contact the manufacturer for this information – which can be entered under the custom setting (as below):
The next menu allows you to set the mid-tone values. These should always be set on a colour by colour basis, so make sure the ‘view single gamma only’ box is unchecked. Red, green and blue squares are provided, and a slider under each square should be adjusted until the centre square almost disappears. With this done, the monitor gamma should be entered in the panel, either Macintosh default (1.8) or Windows default (2.2) depending on the platform.
Next, make sure your white point matches that of your monitor. This is when equal values of red, green and blue at full intensity produce white on your monitor screen. This is a pre-set value for all monitors, and is usually a choice of standard CIE colour temperatures. These are: 5000K - D50 or page white 6500K - D65, the accepted Windows default 7500K - D75 9300K - D93, the accepted Mac default
Generally, setting the Mac or Windows defaults will be OK, however the Adobe gamma control panel will allow the white point to be measured approximately. Selecting ‘Measure’ will display three grey squares on screen. Clicking on the left square will add blue to the centre square, whilst the right will add yellow. When the centre square is as neutral a grey as possible, store the measured white point, by clicking the centre square.
With the dark, mid-tone and white points set, your monitor is now calibrated. Store these settings as an ICC or ICM profile that will be called up each time the computer is started up (Macintosh) or each time an ICC compliant application is loaded (Windows). For ease of recognition we would suggest that you call this new profile ‘Monitor Calibration’.
When complete you will see a screen that lets you view the monitor before and after calibration has taken place. Click on the before and the after circles to see the difference. If it looks right click on finish if not click on back and re adjust.
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