Spectral sensitivity of the discoloration of Historical rag paper

• The rate and the magnitude of dis-coloration historical rag paper is inversely proportional to wavelength radiation (Λ). Oxygen concentration [O 2 ] relative humidity (RH) promote discoloration paper. affected by ], RH, Λ, * Λ RH Λ. Tristimulus transformation leads quantitative loss information in assessment. This discusses spectral sensitivity simultaneously Relative Humidity ambient environment. Sacrificial samples were degraded using narrowband sources centred at 450 nm, 525 625 nm combinations two levels: 0% 70% 21% 20% RH. Diffuse reflectance was measured before during degradation experimental runs. Consistent qualitative results obtained for change tristimulus total color CIELAB space. In both cases, increase modelled logarithmically over time. Among three factors investigated this research, (Λ) found have strongest effect. induced most fastest whereas least slowest discoloration. dependence likely be related photo energies different wavelengths, but other played a role. Further analyses revealed that main effects interactions between on statistically significant. It suggests managing power distribution source can crucial collection management.