NCJ Number
113376
Journal
Journal of Forensic Identification Volume: 38 Issue: 5 Dated: (September-October 1988) Pages: 189-196
Date Published
1988
Length
8 pages
Annotation
This article describes the materials and methods for the photographic enhancement of latent fingerprints.
Abstract
A Polaroid MP-4 copy camera was used in the normal (vertical) orientation. Illumination was provided by four, 150 W photofloods. The Polaroid 4x5 bellows and film stage was paired with a 135 mm lens. Images were recorded using Kodak Kodalith Ortho film, type 3 (#2556) 4x5 film or Kodak Precision Line film, LPD-4 4x5 direct image duplication film developed in a similar manner. Both films can be handled and developed under light red safelight illumination in accordance with datasheet recommendations. When using conventional 'direct reflection' techniques, the light source is positioned to give maximum contrast between ridge and furrow. Using the direct reflecting technique, the background reflects while the print deposit absorbs or disperses incident light. The result is that dark ridge detail on a light background can be imaged on film. Normal (black) ridge color is observed. When photographing in the shadow using high-contrast films, greater detail and contrast can often be obtained for ridge structure while background 'noise' in the furrows is subdued. 8 illustrative figures.