the help of coloured filters and adaptable light-guides,
lamps can direct a narrow beam of light at the subject
of the photograph to enhance the object details. Different
light filters also allow for the exposure of distinct
evidence. For example, ultraviolet
light can make stains and fingerprints glow, violet
makes gunshot residue and blood more visible and blue
and green lights are used with enhanced fingerprints
to show up fibres and urine. This is because some materials
absorb the ultraviolet light, while others reflect it,
causing the material to become present under the ultraviolet
light and flash of the camera when the photo is taken.
A crime scene is also documented
by writing down what the scene was like upon discovery,
sketching, videoing, evidence tables to document artifacts
found, voice recording and witness interviews.