NCJ Number
220428
Journal
Journal of Forensic Sciences Volume: 52 Issue: 5 Dated: September 2007 Pages: 1148-1150
Date Published
September 2007
Length
3 pages
Annotation
The study examined the performance of infrared (IR) imaging in examining a number of different substrates for latent evidence that included serial dilutions of bloodstains, writing inks, gunshot residues, and burned documents.
Abstract
The study found that IR can be a simple and effective means of searching for latent trace evidence both at a crime scene and in the laboratory. The process does not destroy evidence, which allows for further testing if required. Findings show that IR can be used to reveal patterns of bloodstains, writing inks, gunshot residue, tire prints, and burned documents. Problems arise, however, when the background substrate and the evidence type absorb IR light to the same degree. This same disadvantage is true for all light-based search methods. Using a range of light sources, including IR, can increase the chance that no latent evidence will go undetected. A Sony F717 or F828 digital camera or Sony DCR-DVD803 digital video camera was used to capture the images under IR illumination. The digital camera should be programmed for IR photography. The "nightshot" mode allowed for a longer shutter speed suitable for IR photography. The IR device on the digital camera or video were used to detect 4 kinds of blood dilution on 10 pieces of black cloth of different material, to detect 81 pen inks on 3 kinds of black cloth, and to detect the distribution of gunshot residue particles at 3 different shooting distances. 2 tables, 5 figures, and 10 references