UV-VIS-IR Imaging Techniques
Many latent fingerprint treatments such as Ardrox, DFO, BY40 and fluorescent powders fluoresce under specific wavelengths of light. Using the DCS 5 multi-wavelength ring light an operator is able to select the optimum wavelength to generate the maximum intensity of fluorescence for each type of treatment.
Interfering backgrounds may be suppressed appearing white as they reflect IR whereas some chemical treatments such as Physical Developer and certain powders absorb IR and appear black. Foster + Freeman’s new fingerprint dusting powder ‘fpNatural 1’ fluoresces brightly in the infrared when illuminated with red light. Its application has the advantage of eliminating interference from most backgrounds which rarely fluoresce at this wavelength.
Reflected UV Imaging
Many surfaces such as glass and plastics absorb UV and appear black, which improves the visibility of both treated and untreated latent prints which often reflect UV. Images can then be significantly enhanced using the DCS5 software.
An integral part of DCS 5 is the easy-to-use software that provides sophisticated image processing and enhancement tools to uncover hidden detail within images.
Operated via simple drop down menus, DCS 5 enhancement software enables the operator to remove textured or ‘difficult’ backgrounds as well as enhance prints developed using a variety of chemical treatments, dyes, stains and dusting powders including the new IR powder.
Each toolbox offers the operator ‘tried & trusted’ enhancement programmes that enable complex processing routines to be performed with a single button press.
Image Validation & Audit Trail
Encryption software protects all original fingerprints captured by the system. Images that are enhanced or processed in any way automatically lose their status of authenticity with full details of each process being recorded in a detailed Audit Trail.
Essential when presenting courtroom evidence, audit trails detail every step taken during the capture and enhancement process together with information about the operator, computer and software used to perform enhancements. Audit Trail descriptions are in simple to follow language to aid presentation.
DCS Wizard provides an interactive step-by-step guide to achieving consistently high quality images of fingerprints.
By following intuitive steps to select the exhibit type, surface type chemical processes, and background data the user will be presented with suggestions on the lighting, filters, excitation wavelengths and camera settings required to achieve the optimum print definition and contrast every time.