Card Set Information

2010-12-15 10:20:10
crime scene

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  1. 2 variations in creating a sketch to document evidence on vertical objects
    • cross-projections or exploded view
    • elevation sketch
  2. how do you fix measurements to surrounding walls in rectangular coordinates
    by measuring at right angles from evidence to surrounding walls
  3. when is baseline appropriate
    exterior scenes without evident landmarks
  4. when are rectangular coordinates on a grid effective
    in gravesite excavations
  5. when should you use triangulation on a baseline
    exterior crime scenes where the field of evidence is not too widely scattered, but there are no adequate landmarks
  6. why is it unnecessary to orient a total station to true north?
    the accuracy of the total station is ridiculously good
  7. 3 things all narratives need
    • 1.detailed with all pertinent facts and conditions documented.
    • 2. accurate with few inferences or subjective evaluations included
    • 3. understandable- logical and organized
  8. why should you mark investigative efforts that yield no results
    to show that effort was expended- lawyer might say there was inappropriate or improper procedures
  9. documenation four key elements
    • 1.notes
    • 2.photo/video
    • 3.sketches
    • 4.reports
  10. how does f-stop affect the resulting photo
    1.smaller f-stop =more light the lens allows in
  11. how to prevent overexposure or bleaching out of close-up photos
    the use of offset flach and oblique lighting in these situations will correct and eliminate this
  12. What can ISO do?
    the higher the ISO= more noise= bad photo
  13. What is the temp. of light measure in?
  14. What is roadmapping?
    patterns overall orientation in the scene and entire pattern (for bloodstain pattern analysis)
  15. Explain f-stop
    f-stop higher=smaller aperture=less light
  16. what does depth of field do?
    relates to the focus of items
  17. what do fill-flash techniques do?
    ensrue consistent lighting across the spectrum.
  18. 3 key elements to consider when evaluating a luminol reaction
  19. what is a positive reaction to blood?
    blue-green, should iniate in a matter of seconds, and remain active for several minutes
  20. what are the three types of evidence that the firearms examiner looks for?
    • 1. layering of trace evidence, indicative of sequence of targets struck
    • 2. damage to the projectile, indicative of the type of target the bullet struck
    • 3. deformation of the projectile, indicative of the angle of impact
  21. why is effective documentation necessary for bloodstain patterns and bullet defects?
    important do destinguish between pieces of evidence. proper numbering is important
  22. If you are not sure if the defect is from a bullet what test can be done?
    chemical tests for examining the presence of copper and lead
  23. What is meant by "origin and cause" when discussing fire scene investigation?
    Determine fire flow and that will help indicate the origin of the fire
  24. What way does firefighting activity affect the fire scene investigation?
    by forcing entry into buildings, vent areas by breaking out windows, tear down walls, or move objects and furniture