Types of Forensic Photographs, Part II

Types of Forensic Photographs

Evidence Establishing Photographs (Mid-Range Photographs)

• Definition: Photographs that capture evidence in context with landmarks to orient viewers to their locations.

• Role: Essential for establishing the spatial relationship of small or indistinct evidence items within a crime scene.

• Purpose:

  • Frames evidence items alongside recognizable landmarks.

  • Helps prevent misinterpretation of the location of small items.

  • Particularly critical when photographing multiple similar items, e.g., shell casings.

Use of Photo Placards

• Description: Items used to label evidence that contributes to clarity in mid-range photographs.

• Effectiveness: Enhances viewers' understanding of evidence positioning.

• Instruction for Use:

  • Create a photograph that captures both the evidence and its associated placard (e.g., item number).

  • Reduce the number of photographs needed by making sure placards are visible in overall shots, thus serving dual purposes.

DIY Evidence Placards

• Recommendations: Use homemade signs if professional supplies are unavailable.

  • Examples:

  • Index cards folded in half labeled with evidence number.

  • Construction flags with evidence numbers.

• Cleanliness: Ensure commercial placards are thoroughly cleansed before reusing to prevent contamination.

Evidence Labeling System

• Importance: Maintain a consistent numbering or lettering system for evidence throughout documentation and reporting.

• Consistency: Use the same identification system throughout the investigation to avoid confusion.

Terminology and Controversy

• Mid Range vs. Evidence Establishing Photograph:

  • Both terms denote the same type of photograph, but “mid range” may imply an incorrect distance context.

  • It suggests a distance-related meaning rather than highlighting the necessity of an established landmark.

  • Emphasizes the central purpose: framing the evidence location alongside a fixed feature rather than adhering to a specific distance.

Perspective in Mid-Range Photography

• Recommendations:

  • Aim for photographs from a natural perspective to maintain proportional representation of evidence.

  • Take mid-range shots immediately before close-up shots to avoid misrepresentation.

• Avoiding Perspective Distortion:

  • Types of Distortion:

  • Lens Distortion: Proper lens type prevents distortion (normal, telephoto, or wide-angle).

  • Photographer's Point of View: Align evidence and fixed features accurately to show their true distances to avoid distortion.

• Composition Techniques:

  • Photograph alignment options:

  • Parallel alignment to the camera's sensor.

  • Linear alignment in the viewfinder.

  • Diagonal formations may occur but are less preferable.

Composition Tips for Mid-Range Photos

• Emphasize filling the frame with relevant subjects while excluding excessive background distractions.

• Examples of Composition Successes and Failures:

  • Good example: Evidence with minimal background.

  • Bad example: Excessive background appearing to distort the actual position of evidence.

Evidence Close-Up Photographs

• Definition: Close-up photographs aimed at capturing detailed aspects of specific items of evidence, also referred to as examination quality or forensic quality photos.

• Key Techniques:

  • Fill the frame with the evidence item of interest to ensure detailed capture.

  • Hold camera perpendicular to the item’s main surfaces to avoid skewed angles.

• Importance of Details: Close-ups should retain the recognizable aspect of evidence while capturing intricate details.

Scale and Placards in Close-Up Photos

• Necessity of Scale:* Include both scaled and unscaled photographs:

  • Unscaled images to eliminate disputes regarding evidence visibility.

  • Scaled images to give a reference for size, useful during analysis and courtroom presentation.

• Careful Positioning: Ensure scales do not obscure any critical evidence when used.

  • Scales must align in height with the plane of the piece of evidence being photographed.

Close-Up Photograph Techniques

• Taking Both Types:

  • First: Photograph the evidence as found (in situ) to capture its condition before any alterations.

  • Second, take additional captures during evidence recovery to cover all sides and angles.

• Consideration of Scale Positioning: The inclusion of scales may require backing away but should allow detailed representation of evidence.

Summary of Evidence Photographing Techniques

• Evidence Photography Strategies:

  • Employ a sequence including evidence establishing, mid-range, then close-up photographs.

• General Reminder: Emphasize consistent approach while avoiding compositional pitfalls such as excessive distraction, distortion, and capturing evidence in its unaltered state.

• Important Reminder: All photographs should aim for clarity and context to aid in investigative processes and legal proceedings.

Next Steps in Study

• Upcoming sessions will cover advanced photography techniques and deeper processing standards in crime scene photography.