Photographic Triad
Definition
The mandatory three-shot sequence for every piece of crime-scene evidence: overall (wide context), mid-range (relational to a fixed scene landmark), close-up (macro of the evidence itself, with and without scale).
- Shot count
- Three per item: overall, mid-range, close-up
- Overall shot
- Establishes wide scene context and orientation
- Mid-range shot
- Ties evidence to a fixed scene landmark
- Close-up shot
- Macro of the item, with and without scale
Common questions
Why is the mid-range shot needed if the overall and close-up already exist?+
The mid-range frame is what lets a court or a later examiner trace an unambiguous path from the wide scene view to the specific item, by anchoring it against a fixed landmark such as a doorway or wall. Without it, a close-up can be challenged as untraceable to a scene location.
Does the triad apply to every single item at a scene?+
Yes, it is applied per item of evidence, not once for the whole scene. A scene with twenty exhibits generates twenty separate triads, each documenting that item's context, position, and detail.
Related terms
- ABFO #2 Scale
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- Alternate Light Source (ALS)
- A device emitting light at selected wavelengths (typically 415 to 535 nm) used to detect biological fluids that fluoresce or absorb light...
- BSA 2023 Section 63
- Bharatiya Sakshya Adhiniyam 2023 Section 63 (the successor to Section 65B of the Indian Evidence Act 1872): the electronic-record certificate that authenticates...
- Oblique Flash
- Off-camera flash held at a low angle (typically 15 to 30 degrees) to the surface plane. Used to highlight impressed evidence (tool...
- Photogrammetry
- A technique that uses overlapping photographs to reconstruct three-dimensional geometry from two-dimensional images. In forensic engineering, photogrammetry and Structure-from-Motion (SfM) software allow...
- Photographic Triad Shot Count
- Minimum examiners-favoured rule: three shots per item of evidence (overall, mid-range, close-up with scale) plus one close-up without scale. The without-scale frame...
- RAW Capture
- Lossless sensor-data file format (Nikon NEF, Canon CR2/CR3, Sony ARW). Preserves the unprocessed image for evidentiary integrity, allows non-destructive white-balance and exposure...