All artificial light sources are intended to simulate daylight and its properties of color rendering or ability of colour discrimination. Two indices, defined by the CIE, are used to quantify quality of the artificial light sources. First is Color Rendering Index which quantifies ability of light sources to render colours and other is the Metemerism Index which describes metamerism potential of given light source. Calculation of both indices are defined by CIE and has been a subject of

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... n and change in past. In this work particularly, the problem of sample number and type used in calculation is addressed here and evaluated. It is noticed that both indices depends on the choice and sample number and that they should be determined based on application.