CFP Forensic Image Metadata & Authentication 2 — Questions and Answers
Question 1: What device should a forensic photographer use when transferring images from a camera's memory card to a computer to prevent unintentional modification of original files?
- A standard USB hub with multiple ports
- A hardware write blocker (Correct answer)
- A wireless Bluetooth adapter
- A cloud synchronization service with version history
Correct answer: A hardware write blocker
A hardware write blocker prevents any write operations to the source media during transfer, ensuring the original files cannot be modified, overwritten, or have their metadata updated.
Question 2: Which EXIF metadata field records the precise date and time a forensic photograph was originally captured?
- ImageDescription
- DateTimeOriginal (Correct answer)
- MakerNote
- UserComment
Correct answer: DateTimeOriginal
The DateTimeOriginal EXIF field records the exact date and time the image was captured in-camera, which is critical for establishing a verifiable forensic timeline.
Question 3: In digital forensics terminology, what is a 'forensic image' distinct from a crime scene photograph?
- An enhanced version of a crime scene photograph prepared for court
- A bit-for-bit exact duplicate of a digital storage device preserving all data (Correct answer)
- A photograph taken using specialized forensic camera equipment
- A digitally signed photograph with a court-assigned evidence stamp
Correct answer: A bit-for-bit exact duplicate of a digital storage device preserving all data
In digital forensics, a 'forensic image' specifically means a bit-for-bit exact duplicate of a storage device, preserving all data including deleted files and file system metadata.
Question 4: What type of log should forensic photographers maintain alongside their image files to document post-processing steps?
- A social media sharing log listing all public disclosures
- A processing notes log documenting all adjustments applied to images (Correct answer)
- A client billing log noting time spent on enhancements
- An equipment depreciation log for tax purposes
Correct answer: A processing notes log documenting all adjustments applied to images
Any post-processing adjustments must be documented in a processing notes log so courts can evaluate how original images were modified and whether modifications are permissible.
Question 5: What does 'non-destructive editing' mean in the context of forensic image processing?
- Editing that cannot be undone once saved to disk
- Processing that preserves the original image file while storing adjustments separately (Correct answer)
- Editing performed without any photographic software or equipment
- Processing that removes all identifying metadata from the file
Correct answer: Processing that preserves the original image file while storing adjustments separately
Non-destructive editing preserves the original image data unmodified while any adjustments are stored in a separate layer or sidecar file, ensuring the original can always be verified.
Question 6: Which ongoing practice best ensures forensic image files remain authentic during long-term storage?
- Periodically re-compressing images to save storage space on the evidence server
- Converting all images to JPEG for universal compatibility across review platforms
- Periodically recomputing and verifying hash values against the original recorded baselines (Correct answer)
- Removing embedded metadata annually to protect investigator privacy
Correct answer: Periodically recomputing and verifying hash values against the original recorded baselines
Periodically recomputing and verifying hash values against the original baselines confirms stored images have not been corrupted or altered over time, maintaining evidentiary integrity.
Question 7: What is the purpose of maintaining a 'working copy' of forensic photographs separate from the original evidence files?
- To replace the original automatically if it is accidentally deleted
- To allow examination and analysis while keeping the original evidence untouched (Correct answer)
- To share with media outlets before court proceedings begin
- To reduce file size for email transmission to the prosecutor
Correct answer: To allow examination and analysis while keeping the original evidence untouched
A working copy allows investigators to examine, enhance, and annotate images without risking any modification to the original evidence file, which must remain pristine.
CFP Forensic Image Metadata & Authentication 2
What device should a forensic photographer use when transferring images from a camera's memory card to a computer to prevent unintentional modification of original files?