A versatile microfadometer for lightfastness testing and pigment identification

Andrew Lerwill; Joyce H. Townsend; Haida Liang; Stephen Hackney; Jacob Thomas

doi:10.1117/12.726029

16 July 2007 A versatile microfadometer for lightfastness testing and pigment identification

Andrew Lerwill, Joyce H. Townsend, Haida Liang, Stephen Hackney, Jacob Thomas

Proceedings Volume 6618, O3A: Optics for Arts, Architecture, and Archaeology; 66181G (2007) https://doi.org/10.1117/12.726029
Event: Optical Metrology, 2007, Munich, Germany

Abstract

The design and experimental method for the use of a novel instrument for lightfastness measurements on artwork is presented. The new microfadometer design offers increased durability and portability over the previous, published design, broadening the scope of locations at which data can be acquired. This reduces the need for art handling or transportation in order to gain evidence-based risk assessments for the display of light-sensitive artworks. The instrument focuses a stabilized high powered xenon lamp to a spot 0.25 millimeters (FWHM) while simultaneously monitoring color change. This makes it possible to identify pigments and determine the lightfastness of materials effectively and non-destructively. With 2.59mW or 0.82 lumens (1.7 x10⁷ lux for a 0.25mm focused spot) the instrument is capable of fading Blue Wool 1 to a measured 11 ΔE_ab value (using CIE standard illuminant D65) in 15 minutes. The temperature increase created by focused radiation was measured to be 3 to 4°C above room temperature. The system was stable within 0.12 ΔE_ab over 1 hour and 0.31 ΔE_ab over 7 hours. A safety evaluation of the technique is discussed which concludes that some caution should be employed when fading smooth, uniform areas of artworks. The instrument can also incorporate a linear variable filter. This enables the researcher to identify the active wavebands that cause certain degradation reactions and determine the degree of wavelength dependence of fading. Some preliminary results of fading experiments on Prussian blue samples from the paint box of J. M. W Turner (1755-1851) are presented.

Citation Download Citation

Andrew Lerwill, Joyce H. Townsend, Haida Liang, Stephen Hackney, and Jacob Thomas "A versatile microfadometer for lightfastness testing and pigment identification", Proc. SPIE 6618, O3A: Optics for Arts, Architecture, and Archaeology, 66181G (16 July 2007); https://doi.org/10.1117/12.726029

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available