Photography Flashcards
General photos are taken when?
take of the scene prior to processing
do crime scene photographers need to be trained?
yes, but they do not need to be a professional photographer
before images are taken what should be considered?
- is the scene safe?
- do you need PPE?
- do you have authority?
- what type of scene is it?
in what order should photographs be taken?
general to specific
What are overall photos?
- street, field, house, hallway or a room,
- give context to the evidence
what are the 4 necessary photographs?
- overall
- midrange
- close-up
- close-up with scale
what type of camera is needed
digital single lens reflex (DSLR)
what does CCD stand for?
charged coupled device.
what is a CCD?
digital equivalent of film, contains millions of silicon photo sensors, each photo sensor is a pixel, the image passes through lens and is focused onto a CCD
what does JPEG stand for?
joint photographic experts group
what does TIFF stand for?
tagged image file format
what is RAW?
proprietary format this is original data aka the digital “negative”
what is the exposure?
amount of light that reaches the CCD
if a photo is over exposed what will the picture look like?
very bright/white
if a photo is under exposed what will the picture look like?
very dark/ black
what camera settings affect the exposure?
- aperture
- shutter speed
- ISO
How is aperture written
As an F number.
what lets in more light in aperture: F4 or F32?
F4
what is the shutter speed?
length of time the camera shutter stays open exposing light onto the camera sensor
what is the longest shutter speed setting?
30 seconds
what is the longest shutter speed without camera shake?
1/60
what is ASA/ISO
numerical rating that describes the sensitivity to light of CCD/Film
this brightens the photo after the sensor has been exposed to light
what happens when you raise the ISO?
gets brighter and also grainier
what is the depth of field?
distance between the closest and farthest objects in a photo that appear acceptably sharp
what affects the depth of field?
- distance from the subject to the camera
- focal length of the lens
a lens with a ___ (Long/short) focal length produces a shallow depth of field.
long
a lens with a ___ (Long/short) focal length produces a deep depth of field.
short
lens focal length tells us what?
- angle of view
- magnification
what does TTL mean?
through the lens
what does TTL do?
pre-flash occurs and this measures the amount of light needed for the actual exposure.
what are the flash techniques?
- direct
- feathered
- fill in
- bounce
- oblique
- multiple flash (on camera)
- multiple flash (off camera)
what is direct flash?
pointed directly at the subject/item you want to photograph, mounted on top of the camera on the hot shoe
what is feathered flash?
flash is off camera held above the lens, pointed into the scene (usually pointed 2/3 downwards)
what is fill-in flash and when do you use it?
fills in shadows to make it not dark under items,
used on bright sunny days
what is bounce flash?
less contrast, softer lighting flash is overhead typically set to 45 deg angle
what is oblique flash and when is it used?
held at an angle to show detail by creating shadows
used for impression evidence typically
what is multiple flash (on), and when is it used?
activated manually flashes several time with long exposure,
used for low light/no light scenes
what is ring flash, and what is it used for?
spreads even light by attaching to the front of the lens, good for macro photography
what is multiple flash (off), and when is it used?
painting with light, long exposure and typically with bulb setting,
sometimes with portable flash unit
used for large outdoor scenes with little light
How do you photograph fingerprints?
overall, mid-range, and close-up
oblique lighting
fill the frame
macro lens
How do you photograph tire tracks?
capture as much of the rotation as possible
width is as important as the pattern
How do you photograph assault victims?
be considerate of the person and maintain privacy and dignity
How do you photograph bite marks?
capture as much detail as possible
small depth of field
slow ISO (~100)
How do you photograph vehicles?
start with exterior
- include each side, corner, licence plate, VIN, decals, any damage or custom accessories
photo the interior
- start with the front drivers, each door, steering column, glove box, instrument panel, rear seat, and trunk
should video be narrated?
no
why would an investigator use video?
to tie different elements together and get a quick overview of a complex scene
how many photos do you need?
as many as needed
what do you need to think about before photographing?
- purpose
- relationship to overall scene?
- relationship to other items
- proper exposure
- will there be reflections
- will photo be explainable/useful
- is it the correct equipment
what is the overall (outside) photo?
establishes location, usually the outside, includes: street signs, apartment complex name, address plaque, identifying landmark.
if a scene is very large what is one way an overall scene photo is taken
with a drone aerial.
what is an overall (inside) photo?
view of the entrance, 4 corners of each room
what is the midrange photo
meant to draw attention to only that one particular piece of evidence
what is the close-up photograph?
show how individual evidence looked at the scene, finer detail is needed
used for comparison purposes, may contain a label that includes exhibit #, date, name, and badge #
what are follow up photos?
additional details and further photos taken at the forensic unit,
may be a thorough seach of exhibits ie the contents of pockets or backpacks
for death scenes what is also photographed?
after the body is removed surfaces beneath body should be photographed
what are the three major points of qualification of a photograph in court?
relavent photo contents
photo must not be prejudicial
free from distortion and not misrepresented
