A light generating system comprising (i) an array of n light generating devices , wherein n≥20, and (ii) a control system configured to control the light generating devices , wherein: - the array of n light generating devices comprises m first light generating devices and k second light generating devices ; wherein the second light generating devices are disposed in an at least partly random arrangement within the array of plurality of light generating devices; wherein m≥10; k≥3; and 2≤m/k≤5; wherein the first light generating devices are configured to generate first device light and wherein the second light generating devices are configured to generate second device light ; - in an operational mode: - the control system is configured to control g 1 first groups of the first light generating devices , wherein 1≤g 1 <b, wherein b=g2, wherein each first group of the first light generating devices comprises gn first light generating devices , wherein g 11 for each first group is individually selected from the range of b≤g 11 ≤m, and wherein the sum of all g 11 's is m; - the control system is configured to individually control g 2 second groups of the second light generating devices , wherein 2≤g 2 ≤k, wherein each second group of the second light generating devices comprises g 22 second light generating devices , wherein g 22 for each second group is individually selected from the range of 1≤g 22 ≤k-1, and wherein the sum of all g 22 's is k; - a lighting parameter of the second device light of respective second groups of second light generating devices of q2 second groups of the second light generating devices changes mutually non-synchronically with time, wherein 2≤q2≤k. - the array of n light generating devices comprises m first light generating devices and k second light generating devices ; wherein the second light generating devices are disposed in an at least partly random arrangement within the array of plurality of light generating devices; wherein m≥10; k≥3; and 2≤m/k≤5; wherein the first light generating devices are configured to generate first device light and wherein the second light generating devices are configured to generate second device light ; - in an operational mode: - the control system is configured to control g 1 first groups of the first light generating devices , wherein 1≤g 1 <b, wherein b=g2, wherein each first group of the first light generating devices comprises gn first light generating devices , wherein g 11 for each first group is individually selected from the range of b≤g 11 ≤m, and wherein the sum of all g 11 's is m; - the control system is configured to individually control g 2 second groups of the second light generating devices , wherein 2≤g 2 ≤k, wherein each second group of the second light generating devices comprises g 22 second light generating devices , wherein g 22 for each second group is individually selected from the range of 1≤g 22 ≤k-1, and wherein the sum of all g 22 's is k; - a lighting parameter of the second device light of respective second groups of second light generating devices of q2 second groups of the second light generating devices changes mutually non-synchronically with time, wherein 2≤q2≤k. <EOS>