## 4 Discussion  
As demonstrated by the results shown in Figure 10, multichannel LED luminaires achieve excellent color discrimination, obtaining a score higher than 80% for all hue ranges. These luminaires are surpassed only by daylight--CIE D65 and CIE D50--in red to yellow hues, and by cool LED luminaires--LED 5500 K (LED55)--in green to blue hues. This is because the daylight spectrum is richer in the long wavelength range, and cool LED lamps provide more energy in the blue-green range. However, it is important to note that the proposed multichannel spectra allow for lower photodegradation compared to the aforementioned light sources, thereby preserving artworks more effectively. The overall analysis of color discrimination, shown in Figure 11, confirms the good performance of the multichannel lighting system, achieving an average score of 86.8%.  
Regarding chromaticity fidelity, and as deduced from Figure 12, the multichannel system achieves an average score of 88.6%, with exceptional performance--over 90%--in the color range from green to blue. This score is only surpassed by overcast daylight (CIE D65) and cool LED lamps (LED 5500 K), although these light sources, as previously mentioned, result in shorter preservation of artworks. Additionally, in terms of hue deviation, the multichannel luminaire achieves a fidelity of 80.0%, higher than that of the other light sources, demonstrating its great potential in color rendering due to its balanced spectral distribution.  
The excellent results in color discrimination and fidelity provided by the multichannel lighting system are evident in the responses from participants in the subjective trial conducted at the Cathedral of Seville. Observers, as shown in Figure 13, prefer neutral or warm light, influenced by the surrounding spaces linked spatially to the Museum of the Cathedral and the Evangelist Chapel. The spectral power distribution of the multichannel luminaire system produces a neutral correlative color temperature (CCT), compatible with lighting systems emitting warm-colored light used in the adjacent chapels. Quantitatively, as illustrated in Figure 13, 40.0% of the observers perceive the color appearance as neutral, and 44.5% find it satisfactory or very satisfactory. Therefore, the proposed lighting control system not only ensures suitable color rendering and hue discrimination but also provides adequate comfort for observers, aiding in the preservation of artworks in heritage environments.  
It is important to note that color quality--encompassing both color fidelity and hue discrimination--is not the only factor influencing the perception of artworks or altar pieces. Luminance uniformity, along with the minimization of glare, also plays a crucial role in accurately reproducing heritage objects. Therefore, the placement of spotlights in relation to the observer's position is critical for enhancing the optimal perception of the artwork. This is particularly important because the specular reflection from the varnish on paintings can redirect light and create glare, potentially impairing visual appreciation.  
The proposed multichannel luminaire system introduces a novel approach for enhancing both the color rendering and preservation of artworks in heritage environments. The study presented is limited to the specific case studies described in the methodology; therefore, further analysis is needed to assess its effectiveness under different conditions. Nevertheless, the potential of this new lighting system offers a valuable tool for improving the perception and preservation of architectural heritage.