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We tried to group together the more usual questions we receive about using and interpreting this site data and services. These FAQs are all related to the EasyRGB site and the way we specifically handle color information. If you are searching for more generic information about color, on the Net there are several good sites devoted to color science, physics, psychology, physiology and technology. Check our Links page for a list of handy color FAQ references.

What can I do using the services of this site?

How accurate are on-screen colors?

How are color standards measured?

How color measures are stored in the EasyRGB database?

How is the closest color (best match) calculated?

Why HLS/HSL/HSB/HSV data is not supported?

Is any gamma correction applied to the displayed colors?

Modern CRT and LCD monitors should be standardized in RGB response as specified in Rec. ITU-R BT.709. This agreement is internationally accepted and is the basis for the future HDTV.
To adhere to this standard de facto, we use the Rec. ITU-R BT.709 transfer function. This is the best solution for PC based browsers. In our experience the same correction works well for Mac and WebTV users.
In the Mac world a lot of discussions were around about the way "QuickDraw" intrinsically applays gamma correction. Frankly speaking we are not very familiar with the Mac environment but the results we experienced on browsers running on Mac were pretty good and at the time did not required any special adjustment.
The calculations are based on a D65 illuminant and a 2° observer. XYZ values of the white point (0 to 1) have been rounded to 5 decimal digits.


Why is a 45 (not a sphere based) spectrophotometer used?

Is possible to add a new color collection to the color matching list?

What is the required color resolution for this site?

Is any compatibility problem associated with old browsers?

Why printed colors are not consistent with my monitor?