A study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographs

Abstract Silver gelatine photographs were the most dominant photographic process of the twentieth century from the 1880s until the 1960s. They are prone to yellowing, mirroring and fading which is largely attributed to the effects of pollutants, relative humidity and residual processing chemicals. E...

Full description

Bibliographic Details
Main Authors: Jacqueline Moon, Katherine Curran
Format: Article
Language:English
Published: SpringerOpen 2017-11-01
Series:Heritage Science
Subjects:
Online Access:http://link.springer.com/article/10.1186/s40494-017-0159-9
_version_ 1819138620222603264
author Jacqueline Moon
Katherine Curran
author_facet Jacqueline Moon
Katherine Curran
author_sort Jacqueline Moon
collection DOAJ
description Abstract Silver gelatine photographs were the most dominant photographic process of the twentieth century from the 1880s until the 1960s. They are prone to yellowing, mirroring and fading which is largely attributed to the effects of pollutants, relative humidity and residual processing chemicals. Experts in the conservation of photographs claim they can determine the causes of deterioration with the naked eye: the effects of humidity result in a more yellowed appearance, whilst the presence of residual chemicals results in a redder appearance. This work aims to investigate if the same deterioration processes can be diagnosed in photographic prints with a spectrophotometer by addressing two questions: (1) In new and artificially aged silver gelatine photographs is it possible to distinguish between discolouration caused by silver migration and that caused by the presence of residual sulfur? (2) What are the complexities of applying these findings to historic photographs? A set of test photographs, some well processed and some insufficiently washed was developed and artificially aged. These were compared to a small collection of historical photographs of different ages, paper types and image colours. Samples were assessed using visual observation, residual silver and hypo spot tests, colour measurements including L*a*b* and reflectance spectra, Fourier transform infra-red (FTIR) spectroscopy and transmission electron microscopy (TEM). After artificial ageing the well processed test photographs were more yellowed, TEM indicated that this was due to colloidal silver formation. The insufficiently washed test photographs were more red but also darker, TEM showed these samples to have more homogeneous silver filaments, thought to be due to silver sulfide formation. The results for the historical photographs were similar but more subtle. A larger sample set is needed to investigate this more extensively. Further investigation on historical samples, with colour measurements and residual silver and fixer spot tests will take place.
first_indexed 2024-12-22T11:09:40Z
format Article
id doaj.art-3892627451084fe2a6d7f3b79fac2d56
institution Directory Open Access Journal
issn 2050-7445
language English
last_indexed 2024-12-22T11:09:40Z
publishDate 2017-11-01
publisher SpringerOpen
record_format Article
series Heritage Science
spelling doaj.art-3892627451084fe2a6d7f3b79fac2d562022-12-21T18:28:11ZengSpringerOpenHeritage Science2050-74452017-11-015111510.1186/s40494-017-0159-9A study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographsJacqueline Moon0Katherine Curran1The National ArchivesUCL Institute for Sustainable Heritage, Bartlett School of Environment, Energy and Resources, University College LondonAbstract Silver gelatine photographs were the most dominant photographic process of the twentieth century from the 1880s until the 1960s. They are prone to yellowing, mirroring and fading which is largely attributed to the effects of pollutants, relative humidity and residual processing chemicals. Experts in the conservation of photographs claim they can determine the causes of deterioration with the naked eye: the effects of humidity result in a more yellowed appearance, whilst the presence of residual chemicals results in a redder appearance. This work aims to investigate if the same deterioration processes can be diagnosed in photographic prints with a spectrophotometer by addressing two questions: (1) In new and artificially aged silver gelatine photographs is it possible to distinguish between discolouration caused by silver migration and that caused by the presence of residual sulfur? (2) What are the complexities of applying these findings to historic photographs? A set of test photographs, some well processed and some insufficiently washed was developed and artificially aged. These were compared to a small collection of historical photographs of different ages, paper types and image colours. Samples were assessed using visual observation, residual silver and hypo spot tests, colour measurements including L*a*b* and reflectance spectra, Fourier transform infra-red (FTIR) spectroscopy and transmission electron microscopy (TEM). After artificial ageing the well processed test photographs were more yellowed, TEM indicated that this was due to colloidal silver formation. The insufficiently washed test photographs were more red but also darker, TEM showed these samples to have more homogeneous silver filaments, thought to be due to silver sulfide formation. The results for the historical photographs were similar but more subtle. A larger sample set is needed to investigate this more extensively. Further investigation on historical samples, with colour measurements and residual silver and fixer spot tests will take place.http://link.springer.com/article/10.1186/s40494-017-0159-9Silver gelatine photographYellowingImage silverSilver filamentsColloidal silverTransmission electron microscopy
spellingShingle Jacqueline Moon
Katherine Curran
A study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographs
Heritage Science
Silver gelatine photograph
Yellowing
Image silver
Silver filaments
Colloidal silver
Transmission electron microscopy
title A study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographs
title_full A study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographs
title_fullStr A study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographs
title_full_unstemmed A study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographs
title_short A study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographs
title_sort study of the relationship between the migration of image silver and perceived yellowing of silver gelatine photographs
topic Silver gelatine photograph
Yellowing
Image silver
Silver filaments
Colloidal silver
Transmission electron microscopy
url http://link.springer.com/article/10.1186/s40494-017-0159-9
work_keys_str_mv AT jacquelinemoon astudyoftherelationshipbetweenthemigrationofimagesilverandperceivedyellowingofsilvergelatinephotographs
AT katherinecurran astudyoftherelationshipbetweenthemigrationofimagesilverandperceivedyellowingofsilvergelatinephotographs
AT jacquelinemoon studyoftherelationshipbetweenthemigrationofimagesilverandperceivedyellowingofsilvergelatinephotographs
AT katherinecurran studyoftherelationshipbetweenthemigrationofimagesilverandperceivedyellowingofsilvergelatinephotographs