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This test may be affected by your operating system color profile.
This is a gamma calibration test image. The gamma defines how the luminance (the amount of light) on the screen depends on the 8-bit RGB values. As of 2007, computer monitors are supposed to adhere the sRGB standard, which is very similar to a gamma value of 2.2. Especially for things like photo editing it is important that your gamma settings are correct, since this is what digital cameras and photo printers are supposed to approximate.
Look at the image below, and take a few steps back from your monitor such that you don’t see the individual pixels or squint your eyes. In each of the vertical color bars, the lighter and darker bands should blend in at the height labeled “2.2″, which is the gamma setting. Actually, for a true sRGB display, the bands should blend in at 2.25 (48%), 2.20 (25%), and 2.17 (10%). read more
Background
What it should look like
On the right is what the gamma calibration test image should look like.
Mac users
Note for Mac users: check your system gamma for this test; it’s under Apple > System Preferences > Displays > Color > Calibrate > Gamma. If it is set to 1.8, of course the test should show a value 1.8.
read more Adjusting the video card driver
These PNG images are without embedded gamma information. I believe that the test works, even in browsers with broken gamma support such as Internet Explorer 6 and 7. For more information about gamma (links open in new window):
- Gamma correction (wikipedia)
- sRGB color space (wikipedia)
- The PNG Gamma dilemma - Gamma problems with IE and Safari.
