Thanks for the explanation Claas! Peter From: Claas Bickeböller via colorsync-users <colorsync-users@lists.apple.com> Date: Tuesday, 16 July 2024 at 7:22 PM To: Colorsynclist <colorsync-users@lists.apple.com> Subject: Re: Why 2 degree observer measurements for ICC profiles? Hi Peter, The difference between the 2° and 10° observer is basically the size of the area on your retina that is stimulated. For the 2° observer mainly the cones in the center of the retina are stimulated while for the 10° observer also the rods are stimulated. That leads to a difference in color perception. Here is a quite nice visualization: https://santhalakshminarayana.github.io/images/color-science/standard-observ... The type of application when our perception is like a 2° observer or a 10° observer respectively is closely related to the viewing distance. When you look at a printed product from a typical viewing distance of 50-60cm the field of view is close to 2°. That's why for ICC profiles that are mainly used for print applications the 2° observer is the standard. When you look at other products like let's say a painted wall the filed of view is close to 10°. The wording on our website is a little misleading I must admit. Most of our industrial products are used for applications where the viewing distance leads to a field of view where the 10° observer correlates better than the 2° observer. BTW, when you want to check if in a certain situation "you are" the 2° or the 10° observer there is a simple test. Stretch out your arm, thumb upwards and look at your thumb with one eye. The area that is covered corresponds to approximately 2°. If the area can be covered with the entire fist, this is approximately 10°. Best regards Claas Peter Miles via colorsync-users schrieb am 16.07.24 um 04:13:
Hi list members. Hoping some color science folk out there on the list could help answer a question I have.
From Konica Minoltas web page titled “Understanding standard observers in color measurement” “CIE standard observers help correlate instrumental color measurements to human visual assessments. The 1964 10 Degree Supplementary Standard Observer is considered to be more representative of how the human eye perceives color.”
So why do ICC profiles, for print production, still use 2degree observer measurements instead of 10 degree observer measurements? Given that the 10 degree observer “is considered to be more representative of how the human eye perceives color. (me: Than 2 degree observer)”
Thanks Peter