CSI Electronic Surveillance Systems 2 — Questions and Answers
Question 1: Which camera technology provides the best image quality in near-total darkness without emitting visible light?
- Day/night CCD cameras
- Thermal infrared cameras (Correct answer)
- Intensified CCD cameras
- Standard color cameras
Correct answer: Thermal infrared cameras
Thermal infrared cameras detect heat signatures rather than visible light, providing imaging in complete darkness without any illumination.
Question 2: In CCTV surveillance, what does 'dwell time' refer to?
- The time a camera takes to refocus
- The time a PTZ camera remains on a preset position before cycling (Correct answer)
- The delay between recording and playback
- The lifespan of a recording medium
Correct answer: The time a PTZ camera remains on a preset position before cycling
Dwell time is the duration a pan-tilt-zoom camera pauses at each preset position during an auto-patrol sequence before moving to the next.
Question 3: An investigator notices a surveillance camera with a very narrow field of view but extreme detail at long range. This is most likely equipped with a:
- Wide-angle lens
- Fisheye lens
- Telephoto lens (Correct answer)
- Varifocal lens
Correct answer: Telephoto lens
Telephoto lenses have long focal lengths that magnify distant subjects while narrowing the field of view, ideal for long-range detail capture.
Question 4: What is the primary legal concern when conducting covert video surveillance in a workplace?
- Camera resolution requirements
- Employee expectation of privacy in certain areas (Correct answer)
- Federal licensing for recording equipment
- Mandatory union notification periods
Correct answer: Employee expectation of privacy in certain areas
Employees retain an expectation of privacy in areas such as restrooms and locker rooms, and covert surveillance in these areas is illegal regardless of employer authorization.
Question 5: Which type of transmission is most susceptible to interception when used in a wireless surveillance system?
- Fiber optic
- Coaxial cable
- Unencrypted 2.4 GHz RF (Correct answer)
- Twisted pair with encryption
Correct answer: Unencrypted 2.4 GHz RF
Unencrypted 2.4 GHz RF transmissions can be intercepted with readily available equipment, making them the least secure transmission method listed.
Question 6: A digital video recorder (DVR) uses H.264 compression. Compared to older MPEG-2, what is the main advantage?
- Higher frame rates only
- Smaller file sizes at equivalent image quality (Correct answer)
- Compatibility with analog cameras only
- Faster playback speeds
Correct answer: Smaller file sizes at equivalent image quality
H.264 achieves significantly smaller file sizes than MPEG-2 at the same image quality level, allowing longer storage retention or less storage space.
Question 7: When establishing a surveillance post, the term 'backstop' refers to:
- A secondary recording device
- The background behind a subject that identifies their location (Correct answer)
- A camera mounted behind the primary camera
- Legal authorization to conduct surveillance
Correct answer: The background behind a subject that identifies their location
A backstop is the background visible behind a surveillance subject, used to confirm location and provide context for identification in recorded footage.
CSI Electronic Surveillance Systems 2
Which camera technology provides the best image quality in near-total darkness without emitting visible light?