Photography and plan drawing (3)

A Digital Image Is?

A visual representation of a scene that is stored as electronic data
rather than on photographic film

Give some examples of a digital image

• DSLR photographs
• Mobile phone photographs
• Videos
• CCTV images .
• Body worn video footage
• 360° scene captures

effect of more pixels

higher image resolution = more detail

what is resolution

This refers to the number of pixels in width and height

Difference between JPEG and TIFF/RAW

JPEG = smaller, some image compression (loss of quality)

TIFF/RAW = much larger all original data kept ideal for forensic use

Explain metadata

Digital images automatically store hidden data (EXIF), like:
1. Date and time the photo was taken
2. Camera settings (aperture, shutter speed, ISO)
3. GPS location (if enabled)

4. Camera make and model

5. 5. Resolution
   
   

What does metadata help prove

image’s authenticity

chain of custody

continuity

audit trials

List the capture order of photographs (7)

1 PHOTONAME PLATE
2 EXTERIOR OFSCENE
3 APROACH TO THE SCENE
4 ROUTE OFFENDER MAY HAVE TAKEN
5 INTERIOR OF SCENE INCLUDING QUARTERING
6 LONG, MID, CLOSE UP IMAGES
7 COMPARISON PHOTOGRAPHS

How do we ensure we document the whole scene?

Quarter the scene
Overlapping shots
Fill in the Gaps
Small spaces
Look up!
Evidence location

How can you uniquely identify a vehicle

Chassis or Vehicle Identification Number (VIN)

What Is Composition in Crime Scene Photography?

• Composition refers to how elements are arranged within a photograph
• what you include in the frame, how close or far you are, and the angle you shoot from

good composition is ensuring the image is what?

• Clear
• Accurate
• Useful for analysis or court

Why Do We Draw Crime Scene Sketches?

• Shows the Layout Clearly
• Accurate Measurements
• Clarifies Relationships Between Evidence
• Supports Memory and Documentation
• Used as Court Evidence

How to Sketch a Crime Scene

• Record of the scene in plan format
• Dimensions and distances
• 2 Fixed points

What does higher resolution images allow

• Capture more detail

• greater enlargement without loss of quality

• Support closer examination of evidential features