This Little Light of Mine: An Investigation into the Effects of Different Light Sources on MFT Data

With different types of microfade testers (MFTs) being employed by heritage institutions, all of which can be configured based on desired application, confidence that data collection accurately reflects reality as closely as possible is necessary. The specific configuration of the instrument, such as the light source, can impact this. Xenon arc lights have traditionally been used; however, light-emitting diodes (LEDs) have become a popular alternative as their use in gallery lighting has increased. While both have advantages and disadvantages, LEDs specifically can have performance instability and notably have variable spectral power distributions (SPDs) with spikes and troughs within the visible range, particularly in the high energy visible area (400-500 nm). Different coloured materials can display more sensitivity to specific wavelengths of light; therefore, if the material’s reactive wavelengths coincide with spikes or troughs in the SPD, the results may be disproportionate. This study investigates the fading behavior of select garments from LACMA’s collection to be included in the upcoming exhibition Dressed for Change: Chinese Women’s Fashion, 1875–1960s, comparing the results from xenon arc light – and LED-based MFTs. The findings present foundational research on the potential for test condition dependent misinterpretation of MFT results and explore the broader implication for the analysis of collection objects.