title: Latent Fingermark Aging Patterns (Part II): Color Contrast Between Ridges and Furrows as One Indicator of Degradation.
abstract: Currently, no established methodology exists to determine degradation patterns of latent fingermarks by visual means. This article is the second in a series of reports exploring quantifiable degradation-related parameters, which focuses on color contrast changes between fingermark ridges and furrows over time. Experiment variables included type of secretion (eccrine and sebaceous), substrate (glass and plastic), and exposure to natural light (dark, shade, and direct light). Fingermarks were sequentially visualized with titanium dioxide powder and photographed. Image histogram profiles were evaluated and combined with statistical analysis of color data values. Results indicate that sebaceous depositions on glass were generally less degraded by the effect of environmental conditions compared with those on plastic. In addition, aging in darkness was not always the best condition for preservation, and direct exposure to light seemed to inhibit visual degradation under certain conditions. Overall, the technique provided sufficient sensitivity to discern degradation patterns of fingermarks.
authors.affiliation: Legal Medicine Unit, Faculty of Medicine, University of Barcelona, C/Casanova 143, 08036 Barcelona, Catalonia, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: De Alcaraz-Fossoul
authors.affiliation: Legal Medicine Unit, Faculty of Medicine, University of Barcelona, C/Casanova 143, 08036 Barcelona, Catalonia, Spain.
authors.forename: Carme
authors.initials: C
authors.lastname: Barrot Feixat
authors.affiliation: Legal Medicine Unit, Faculty of Medicine, University of Barcelona, C/Casanova 143, 08036 Barcelona, Catalonia, Spain.
authors.forename: Jack
authors.initials: J
authors.lastname: Tasker
authors.affiliation: The Corner House Business Centre, Forensic Focus Ltd., 2 Albert Road, Ripley, Derbyshire DE53FZ, UK.
authors.forename: Luke
authors.initials: L
authors.lastname: McGarr
authors.affiliation: The Corner House Business Centre, Forensic Focus Ltd., 2 Albert Road, Ripley, Derbyshire DE53FZ, UK.
authors.forename: Karen
authors.initials: K
authors.lastname: Stow
authors.affiliation: Legal Medicine Unit, Faculty of Medicine, University of Barcelona, C/Casanova 143, 08036 Barcelona, Catalonia, Spain.
authors.forename: Clara
authors.initials: C
authors.lastname: Carreras-Marin
authors.affiliation: Department of Methodology of the Behavioural Sciences, Faculty of Psychology, University of Barcelona, Passeig de la Vall d'Hebron, 171, 08035 Barcelona, Spain.
authors.forename: Jaume
authors.initials: J
authors.lastname: Turbany Oset
authors.affiliation: Legal Medicine Unit, Faculty of Medicine, University of Barcelona, C/Casanova 143, 08036 Barcelona, Catalonia, Spain.
authors.forename: Manel
authors.initials: M
authors.lastname: Gené Badia
keywords: aging; color contrast; degradation; forensic science; latent fingermarks; parameters; patterns