Abstract:
This study investigated the application of chemical imaging to the detection of latent fingerprints using the Condor
macroscopic chemical imaging system (ChemImage Corp., Pittsburgh, USA). Methods were developed and optimised for the
visualisation of untreated latent fingerprints and fingerprints processed with DFO, ninhydrin, cyanoacrylate, and cyanoacrylate
plus rhodamine 6G stain. The results obtained with chemical imaging were compared to the detection achieved using
conventional imaging techniques.
The Condor significantly improved the detection of many prints, especially those that might be considered poor quality or
borderline prints. Prints on newspaper treated with ninhydrin and DFO, and prints on white and yellow paper treated with
ninhydrin, benefited the most from chemical imaging detection. In many cases, fingerprints undetectable using conventional
imaging techniques could be visualised with chemical imaging. Ridge detail from untreated prints on yellow paper was also
detected using the Condor. When prints of high quality were examined, both detection techniques produced quality results.
The results of this project demonstrate that chemical imaging offers advantages over conventional visualisation techniques
when examining latent fingerprints, especially those that would be considered difficult, such as weak prints or prints on surfaces
that produce highly luminescent backgrounds.
Standard testing procedures for the detection and enhancement of fingerprints by chemical imaging are presented and
discussed .
