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Forensic Photography and Digital Imaging
• John R. A. Smith
• Currently Senior Lecturer in Imaging
Science, University of Westminster
• Previously 10 years with Forensic
Science Service’s Serious Crime Unit and
LGC Forensics in UK
• Provides photographic services to
independent forensic science providers
• Provided specialist digital photographic
training to organisation including UK
Home Office, New South Wales Police &
Criminal Investigation Bureau, Taiwan
Forensic Photography and Digital Imaging
• Human vision: how we see colour, tone, contrast, the
limits of human vision
• Digital photography: how cameras record colour, tone,
contrast
• Photography and digital imaging as a visual record and
as an investigative tool
• what is a digital image?
Forensic Photography and Digital Imaging
• The importance of producing accurate records
(perspective, point of view, image magnification)
• How lenses work (focal length, aperture, depth of field,
field of view)
• Exposure (shutter speeds, ISO speeds, the histogram)
• White balance and colour temperature
• Image resolution
• Image formats and file formats
Forensic Photography and Digital Imaging
• Forensic
photography
– legal issues
– audit trails
– archives
Forensic Photography and Digital Imaging
Original image Enhanced image
• Seeing and photographing evidence in the best light
– coloured light and filters for contrast enhancement
• Fluorescence, ultraviolet & infrared examination & photography
• Digital image processing for forensic marks photographers
• Best practice guidelines
Forensic Photography and Digital Imaging
Reflected lightDiffuse light
• What to consider before
attending the crime scene
– choice of equipment
– file formats
– standard operating procedures
• Photographing and documenting
the crime scene
– what to photograph, when and from
where?
– the importance of note taking,
sketches, scales, labels and
evidence markers
Forensic Photography and Digital Imaging
• Photography of
– blood spatter
– injuries and marks on bodies
– fingerprints
– tyre marks and footwear impressions
– other marks
• Evidence preparation and presentation for court
Forensic Photography and Digital Imaging