Science and Heritage Programme

The Lifetime of Colour Photographs in Mixed Archival Collections

Centre for Sustainable Heritage, UCL/ The National Archives

Award holder - Dr Matija Strlic
Student - Ann Fenech


Colour photographic media have attracted and continue to attract considerable research and public interest. This project holistically addresses colour photographic materials as part of complex collections. To develop a tool for management of these collections, inter-disciplinary research encompassing an understanding of history, collection survey, definition of the term ‘lifetime’, and intensive research into material stability, particularly in complex environmental conditions, will be carried out.


To evaluate experimentally the life expectancy of colour photographic media in mixed archival collections, taking into account the principle degradation factors in the storage environments.

  • To establish a reference sample collection.
  • To develop a new chemical analytical methodology for non-destructive characterisation and identification of sensitive photographic materials.
  • To estimate the quantity of colour photographs and assess their condition through a statistical survey of collection of The National Archives, London.
  • To construct a computational model to enable material lifetime prediction, by taking into account material, micro- and macro-environmental parameters.


What is the impact on life expectancy of colour photographic media in mixed archival collections? Which are the principle degradation factors in the storage environments and how can the lifetime of colour photographs be modelled?


In the course of this interdisciplinary project, the problem of material change and lifetime prediction will be addressed through:

  • studies of the history of colour photography,
  • material studies, especially in view of image durability in various environmental conditions,
  • non-destructive material characterisation and identification,
  • modelling, in order to develop a collection management tool.


The principle outcome will be knowledge on colour photographic image durability in mixed collections and under non-standard climatic conditions. A tool will be developed for collection managers to calculate and assess risks associated with the preservation of a collection.


It is estimated that the project will have a particular impact on the archival community, although the modelling tool will be of interest to collection managers in general.


Dr Matija Strlič (UCL) and Dr Nancy Bell (The National Archives)


Ann Fenech

Ann Fenech joined the Centre for Sustainable Heritage, University College London, in September 2008 following a Bachelor of Science (Honours) in Chemistry and Biology at the University of Malta. 

Ann’s project, in collaboration with The National Archives focuses on one of the most unstable carriers of information, chromogenic colour photographic prints. In mixed collections, they are stored in archival folders with other media, predominantly paper. The storage conditions are thus optimised for paper, but how does this affect the lifetime of colour photographic prints?

The apparently straightforward question is actually a very complex one involving environmental and material studies, and studies of how photographic objects are valued.

  • An extensive reference collection of chromogenic colour photographic prints was characterised and a non-destructive near-infrared tool for dating of colour photographic paper was developed.
  • A survey of archival environments allowed for prioritisation of environmental factors.
  • An experimental methodology was devised for simultaneous study of relevant environmental parameters (temperature, humidity and acetic acid concentration)
  • A complex multi-parametric damage function is in development, based on a non-destructive method for monitoring changes in dye concentrations over time.
  • A value-assessment experiment is planned to assess loss of utility value in dependence of image change.

The principle outcome of this highly interdisciplinary study is the first computational collection model based on environmental data, material properties and value assessment. This innovative tool will enable collection managers of mixed archival collections to optimise environmental management strategies while minimising the rate of change (and damage) of colour photographic collections.

Image: Rapid non-destructive characterisation of colour photographs using Near Infrared Spectroscopy (NIR). Image (c) Dr Matija Strlic, Centre for Sustainable Heritage, UCL.



Assessment Workshop - Lifetime of Colour Photographs in Mixed Archival Collections

Heritage Science Laboratory (Gordon House)
29 Gordon Street, London

Have you ever wondered about loss of information in archives caused by material decay? Or about what makes an archival photograph fit-for-purpose?

One of the questions the research project ‘Lifetime of Colour Photographs in Mixed Archival Collections’ aims to tackle is the way material degradation is linked to information content in photographic images. In particular, the point where photographs are no longer ‘fit for purpose’ is of interest.  To understand this better this question will be explored with various groups of stakeholders - curators and custodians to photographic collectors, scientists and the general public - in order to capture a variety of opinions.

The aim of the workshops is to define the point at which changes in information content is no longer considered to be acceptable for photographs in archives. The workshops will start with a brief introduction to the project and the exercise. The assessment exercise will consist of a classification exercise of photographs at different stages of degradation. This will be followed by a brief discussion on any issues arising from the exercise. Following the workshops and data analysis, a report on the results of the workshop will be circulated to all participants.

Workshops will last approximately one hour and are taking place on the following dates:

Monday 4th April 2011 - 4pm              
Monday 11th April 2011 - 4pm              
Friday 15th April 2011 - 4pm              
Thursday 5th May 2011 - 4pm              
Tuesday 10th May 2011 - 5pm              
Friday 13th May 2011 - 1pm          
Friday 13th May 2011 - 4pm

If none of these dates are appropriate, please contact Ann Fenech as further workshops are planned for the future.

To book a place, please go to the Eventbrite website.

Photo sample