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