Gamma check and adjustments

Gamma curve describes the required light intensity for monitor's intermediate output levels. In order for your monitor to display the colors correctly, the intensity of light for intermediate colors should exactly match the gamma curve.

Gamma test, according to sRGB standard (click on the image for enhanced picture)

In the image to the right, you can check whether your monitor displays the gamma curve correctly.

Move away from your monitor (2 meters should be sufficient), or blur your vision, and then check whether the inner part of the displayed gradient bar matches the outer part. The mismatch can be either in color (uncommon) or in intensity (more common), and usually only on some parts of the gradient bar. If there is a mismatch, the boundary between inner and outer parts will become clearly visible.

Look at the following two examples to judge whether your monitor has sufficiently accurate gamma curve. If the gamma curve is sufficiently accurate, we recommend that no adjustments should be made. Adjusting the gamma curve using graphic card's LUT decreases the number of available colors (regardless of the method: both colorimeter and manual adjustment will reduce the number of colors, but this is usually much less noticeable then incorrect gamma curve).

• Left image: Bad gamma curve, intensity mismatch in the bottom part
• Right image: Acceptable gamma curve

Simple adjustment (intensity only)

Locate the 'color settings' - 'gamma curve' adjustment in your graphic card's settings. For nVidia graphic cards, it is located in nVidia Control Panel / Adjust desktop color settings / graph.

On the image below, you can see several squares; below each a value called 'in' or 'x' is displayed. Use this value to find appropriate point on the graph.

Change the 'out' value of the point (by using keyboard's up and down arrow keys) until the inner part of first square matches in intensity with outer part.

Do this for each of the displayed squares, in order from top to bottom and from left to right.

Advanced adjustment (intensity and color)

If the gamma curve mismatch is not intensity based, but color based, you will have to adjust each of the three channels (red, green and blue) separately. The procedure is identical; just select the appropriate color channel.

(Note 1: For adjusting purposes, we recommend that you download and display all images in an image viewer, preferably on a black background, in 1:1 pixel ratio (size 100%))

(Note 2: Internet Explorer 6 & 7 will display the images below incorrectly, so it is necessary to download them and display them in image viewer in 1:1 pixel ratio (size 100%))