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| Recording
The Incident |
| After the crime scene
has been managed and the initial assessment (recording the original
situation and how it was discovered) is complete, the forensic photographers
arrive on the scene. The jury cannot revisit the scene of a crime
during court sessions, so photographs can help to vividly recreate
the scene as well as create a lasting record of the evidence so it
can be properly analysed in a forensic laboratory. |
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Select one of the following topics for more information:
--> Recording
--> The
camera
--> Digital
cameras
--> Video
cameras
--> Techniques
--> Light
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| Recording |
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| Where memory fails, technology has
replaced it, just as crime scene photography and videoing have replaced
baisc memory-based recounts of a crime scene with vivid live shots
of the aftermath.Through this, accuracy is greatly improved and the
film itself becomes a form of evidence. |
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| The
Camera |
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| Forensic photographers usually prefer
to use 35 mm cameras, or medium format, as it tends to balance the
portability and ease of use with quality images. When taking close-up
photos of evidence, the camera is often mounted onto a tripod for
stability to ensure the necessary quality required of photographs
presented as evidence in court. Some forensic labs have their own
darkroom facilities, which then enable photographers to develop the
pictures themselves. |
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| Digital
Cameras |
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| Digital cameras have a number of
advantages when used in forensic photography as they require no chemical
processing, can be displayed on the camera straight after being taken
to ensure that the image was captured and the photos can be immediately
transferred to a computer and stored in the database. However, digital
photos are very easy to alter which therefore prevents them from being
used as evidence in court. |
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| Video
Cameras |
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| Video cameras also provide an easy
and inexpensive way to document crime scenes and can give the jury
with a more realistic sense of the crime scene than still pictures
of a room. The zoom on video cameras are however,more often digital
rather than optical
and thus provide pictures of slightly less clarity than actual photographs.
Videos are in general a good briefing tool for police officers who
have not visited the crime scene. |
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| Techniques |
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Close-up shots of evidence have precise requirements, such as exactness,
angle taken and balance, in order to achieve the best possible shots.
These pictures of evidence form a factual record and must be able
to be reproduced in terms of size, shape and colour, thus, balance
and accuracy is an absolute must. The use of basic camera flash
and flood lights are quite sufficient for general crime scene photography,
but close-up shots of evidence require careful lighting. Artificial
sources of light have proved very useful in the photography of evidence.
An example of this concerns oblique-angled light, whereby the light
is angled or slanted towards the subject. This is used for bringing
out the detail in textured surfaces, such as foot and shoe prints
left in mud.
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| Light |
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| With
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.
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