This paper describes two experiments that were designed to investigate the museum lighting environment in terms of correlated colour temperature and illuminance. The results are reported as visual perceptions and perception zone maps. Experiment 1 was conducted to investigate the impact of the illumination conditions on visual perceptions in a light cabinet. Experiment 2 was the same as Experiment 1, except that it was performed in a museum. The rating scores were combined to establish the perception zone maps on a correlated colour temperature–illuminance plane. Furthermore, two emotional response models, named the visibility model and the warmth model, suitable for museum indoor lighting in small- and large-scale spaces were established. The analytical results indicated that the pleasant zone found in this study partially agrees with Kruithof's rule.

It is possible to assess the damage to artworks by measuring different physical and chemical parameters. One of the most important parameters is colour difference, which is a consequence of chemical changes in the material. CIE 157:2004 ‘Control of Damage to Museum Objects by Optical Radiation’ classifies museum collections into four groups, according to different levels of light fastness. However, these classes were developed from research using traditional light sources. Even though LED technology is becoming more popular, there is no advanced evaluation of colour fading or a colour change test for contemporary artworks. This study established that the CIE 157:2004 method, based on threshold effective radiant exposure, can be applied to an actual ageing test of ultraviolet-blocked light sources including two types of white LEDs and one traditional halogen lamp. The results also present a colour fading model that can be used in museum LED lighting to predict the colour difference in contemporary photographic materials for short- and long-term exhibition. This study also provides a revised light dosage classification of modern photographic materials for museums. Moreover, the verification studies can be used as a conceptual reference for assessing the damage potential of other art materials under the tunable multi-LED system of the future.