Thread: Software Display Calibrators

Although the approach has been abandoned in Adobe Photoshop CS4 and Adobe now specifi¬cally recommend using a third party hardware based display calibrator, earlier versions of Photos hop included a software only display calibrator and profiler applet called Adobe Gamma. The Photoshop install places this in the Windows Control Panel and also installs a short cut in the Start folder to the ! Adobe profile loader.Adobe Gamma attempts to calibrate and profIle a display by eye. First a gradu¬ated brightness scale is used to calibrate the brightness and contrast settings then a series of solid colour I alternate line patterns is displayed.



The center solid patch is adjusted in brightness by eye until it matches the brightness of the alternate lines. Required corrections are then derived from these relative settings and used to construct a profIle. Corel Paint Shop Pro Photo X2 has a similar utility, but improves accuracy by providing adjustment at 5 different brightness levels. Adobe Gamma only corrects at a single brightness level. These 'eyeball' calibrators are perhaps better than nothing, but are not as accu¬rate as the current hardware calibrators. Recent display drivers include controls which can be used to modifY display character¬istic, such as gamma controls. These should be turned off, or left at default values, before (and after) a display is calibrated and profIled.