Stephen Hackney

• BSc Chemistry and Physics
• Consultant at Tate Gallery

Acid-detecting strips (A-D Strips®) available from the Image Permanence Institute (IPI) and third-party suppliers outside the USA were originally developed to detect volatile acids from deteriorating film stock made from cellulose acetate (CA) by using a five-step colour scale to represent acetic acid concentration. The strips are shown here to be...

Acid-detector (A-D) strips were originally developed to assess the deterioration of acetate film stock, but they can also be used more generally within enclosures to detect volatile acidic pollution. A hand-held reflectance spectrophotometer was used to record the colour of individual strips in order to make consistent and reproducible readings. Ca...

Air pollution is one of the environmental influences that degrade cultural heritage objects situated indoors. Other essential influences, such as temperature, relative humidity, and light are often well monitored. The presence of air pollutants is less often measured or included in risk assessment. The MEMORI® technology presented in this paper was...

An investigation for light exposure on pigments in low-oxygen environments (in the range 0-5% oxygen) was conducted using a purpose-built automated microfadometer for a large sample set including multiple samples of traditional watercolour pigments from nineteenth-century and twentieth-century sources, selected for concerns over their stability in...

The protection of paintings and other objects in collections is a major concern for museum administrators, conservators and national authorities. Artwork may get damaged by accumulation of air pollutants inside protective enclosures due to emissions of volatile and semi-volatile compounds from the exposed objects or from the enclosure itself. Relat...

A modified microfading spectrometer incorporating a linear variable filter is used to investigate the wavelength dependence of fading of traditional watercolour pigments, dosimeters and fading standards at a higher spectral resolution and/or sampling than had previously been attempted. While the wavelength dependence of photochemical damage was lar...

The MEMORI project (Grant agreement 265132) was performed in the period 2010-2013. The project was coordinated by NILU-Norwegian Institute for Air Research and included 14 partners, four subcontractors and an advisory end-user group with 8 members. MEMORI aimed at providing the conservation market with innovative, non-destructive, and early warning...

The physico-chemical characterisation of organic-based cultural heritage materials has been performed in several EU projects to establish markers of damage [1], [2]. The work reported here refers to the evaluation and assessment of varnished surfaces, collagen-based materials (parchment and leather), and cellulose-based materials (19th century canv...

This paper presents preliminary studies and work in progress in the framework of two FP7 projects: MEMORI (Measurement, Effect Assessment and Mitigation of Pollutant Impact on Movable Cultural Assets – Innovative Research for Market Transfer) and NANOFORART (Nano-materials for the conservation and preservation of movable and immovable artworks). On...

The mechanical properties of latex paint films containing different volume fractions of TiO2, CaCO3 and kaolin were measured in uniaxial tension over a broad range of temperatures and crosshead speeds. Young’s modulus results in the glassy region are first compared with several micromechanics theories for particle-filled composites containing elast...

The mechanical properties of artists’ acrylic (latex) paint films containing different volume fractions of TiO2, CaCO3 and kaolin were measured in uni-axial tension over a broad range of temperatures and crosshead speeds. Young’s modulus results in the glassy region were first compared with several micromechanics theories for particle-filled compos...

The photo degradation of watercolour drawings prepared with madder lake pigments on gelatine-sized paper was studied by chemiluminometry, viscometry, and colorimetry. A method of recto irradiation and verso measurement was developed to overcome absorption of the emitted photons by the paint layer. A complex relationship between paper substrate, app...

Pollutants and their potential degradation of paintings have been measured for the first time in microclimate frames (mc-frames), which are used to protect paintings. The pollutants that were measured include both inorganic pollutants, which originate mainly from external sources, and organic pollutants from mainly internal sources. Those originati...

The tensile properties of latex coatings were investigated with a set of custom formulated artist-type paints at an age of 1 year. All films in the study contained a poly(methyl methacrylate-cobutyl acrylate) binder exhibiting a glass-transition at approximately 10°C. The viscoelastic behaviour of the latex matrix is first highlighted through a ser...

The content of this report is based on the results achieved during the EU funded project “Improved Protection of Paintings during Exhibition, Storage and Transit” – PROPAINT.The PROPAINT project (SSPI – 044254) is a Specific Targeted Research Project (STREP)within the Thematic Area 8.1. Policy Oriented Research: Scientific Support to Policies, in...

Advanced measurement techniques for the structural diagnostics of artwork are increasingly providing more complex data that needs to be conveyed to conservators in a meaningful way. Holography and speckle interferometry based sensors are commonly used for this application and of these shearography is quite suitable for measurements outside the opti...

The tensile properties of latex paint films containing TiO2 pigment were studied with respect to temperature, strain-rate and moisture content. The purpose of performing these experiments was to assist museums in defining safe conditions for modern paintings held in collections. The glass transition temperature of latex paint binders is in close p...

Shearography is a full-field optical technique used for non-destructive testing and for the measurement of surface strains. This work presents the development of a novel Impact Assessment Procedure (IAP) using shearography to collect the data about the condition of the artwork. This is a multi-step process with the first step being the recording of...

1 Introduction The use of microclimate frames for paintings during exhibition, storage and transport has become common in many European museums. The frames are used to protect the paintings physically, against externally generated pollutants and to give climate buffering. The positive effects are considered to outweigh the negative effects of a...

Tate is undertaking a major research project to assess the effects of anoxic storage on paper-based works of art. The outcomes will include: the design of a safe, affordable anoxic framing system suitable for both storage and display, capable of being incorporated into historic frames; guidelines on materials which would be harmed by anoxia and inf...

The design and experimental method for the use of a novel instrument for lightfastness measurements on an artwork is presented. The new micro-fading spectrometer design offers increased structural stability (which enables portability) and increased versatility over the previous, published design, broadening the scope of locations at which data can...

Photorefractive holographic interferometry is applied to assessment of movable artworks. Its role is to observe tiny signatures resulting from internal artwork characteristics. In the future, the system will be used for both antifraud and restoration.

Shearography is a full-field optical technique usually used for non-destructive testing and for the measurement of surface strains. This work is the development of a novel Impact Assessment Procedure (IAP), using shearography to collect the data about the condition of the artwork. This is a multi-step process with the first step being the recording...

Nowadays the deterioration of cultural heritage is of major concern. Artworks may suffer irreversible changes during transportation or exhibitions. Conservators need to monitor the condition of artwork in a way that responds to these issues. A non invasive and no contact method is required in order to monitor the continuous changes in the artwork....

This paper is one of a series submitted by the Multi-Encode Project consortium and covers the development of holo-graphic interferometry with dynamic photorefractive crystals. The aim of the first phase of the project is to assess the existing techniques for detection of signatures in various types of artworks. The trademark of our technique is a v...

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 transpo...

This is an introductory paper of a recent EC project dealing with research in cultural heritage and aiming to communicate new fields of application for optical metrology techniques. The project is in its initial state and more conclusive information is expected to be available at the time of the perspective conference. Nowadays safety, ethical, eco...

This is one of a series of papers submitted by the Multi-Encode Project consortium (006427 (SSPI)). Shearography, a full-field speckle interferometry technique, is applied to the investigation of movable cultural heritage. For this project a portable shearography sensor was developed, with conventional sensor hardware supported by novel algorithms...

Speckle interferometry techniques with their high resolution full-field measurement capability offer a means of investigating the complex stress-strain behaviour of art objects under relatively low loading conditions. The focus of this paper is the investigation of art samples using the optical techniques of shearography and digital holography. A t...

The use of non-aqueous deacidification procedures as a preventive conservation measure to assist in retarding the deterioration of painting canvases has been suggested by the Conservation Department of the Tate Gallery [1]. The reverse sides of paintings are treated with commercially available MMC solution (methoxy magnesium methyl carbonate). The...

The use of preventive conservation measures to assist in retarding the deterioration of painting canvases has been suggested by the Conservation Department of the Tate Gallery [S. Hackney and T. Ernst, The applicability of alkaline reserves to painting canvases, in Preventive Conservation Practice, Theory and Research, Pre-prints of the contributio...

Preventive conservation measures can help to retard the deterioration of painting canvases. They offer an alternative to accepting the inevitability of the lining process with all its unresolved aspects. Primary protection of canvas is achieved by environmental controls but further significant gains can be made by eliminating any acidity that has b...

A brief description of air pollution and its significance to conservation is followed by an assessment of four methods of measuring gaseous air pollution within museums. Levels of sulphur dioxide, nitrogen dioxide and ammonia were measured at the Tate Gallery, London, and levels of sulphur dioxide were measured at the National Gallery of Ireland an...

Samples of linen canvas prepared in 1956 and kept in the Tate Gallery for 24 years were tested for tensile strength, acidity, reflectance and sulphur content. The samples included both unimpregnated linen and wax/resin impregnated linen. They were arranged so that some had been exposed to light and some protected from it. In addition a number of pi...