CST CCTV Camera Selection & Placement 3 — Questions and Answers
Question 1: What is the primary purpose of a camera's IR cut filter (ICR)?
- To block visible light during daytime to improve color accuracy
- To physically switch between day and night modes for accurate color rendering (Correct answer)
- To increase frame rate in low-light conditions
- To reduce lens flare from artificial lighting
Correct answer: To physically switch between day and night modes for accurate color rendering
The ICR mechanically moves a filter in front of the sensor, blocking infrared in daylight for true color and removing it at night for better low-light sensitivity.
Question 2: For perimeter detection along a fence line, which camera configuration provides the most effective coverage?
- Single wide-angle dome at the fence center
- Multiple narrow field-of-view cameras spaced along the fence (Correct answer)
- One fisheye camera at the corner
- Elevated PTZ camera on a central pole
Correct answer: Multiple narrow field-of-view cameras spaced along the fence
Spacing multiple narrow FOV cameras along the fence creates overlapping coverage zones with enough detail to detect intruders at every point.
Question 3: Which specification indicates a camera's ability to produce usable images in extremely low ambient light without supplemental illumination?
- High signal-to-noise ratio (SNR)
- Low lux rating (Correct answer)
- Wide horizontal field of view
- High shutter speed
Correct answer: Low lux rating
A low lux rating indicates the minimum light level at which the camera can still produce a usable image, with lower values meaning better low-light performance.
Question 4: What placement consideration is critical when installing cameras to monitor ATM machines?
- Camera must be mounted above and behind the user to capture the face (Correct answer)
- Camera should be angled downward from a height over 15 feet
- Camera should be mounted at ATM height pointing directly at the keypad
- Camera must be outside the ATM enclosure only
Correct answer: Camera must be mounted above and behind the user to capture the face
Mounting the camera above and behind the user captures the face during the transaction while avoiding obstruction of the keypad view by the user's body.
Question 5: A camera's horizontal field of view is 90°. If placed in a corridor 10 feet wide, approximately how far from the camera will the image cover the full corridor width?
- 5 feet (Correct answer)
- 10 feet
- 15 feet
- 20 feet
Correct answer: 5 feet
With a 90° horizontal FOV, the half-angle is 45°, so the image width equals the distance from the camera; a 10-foot-wide corridor is fully covered at 5 feet.
Question 6: Which camera feature is most important when the surveillance system must capture evidentiary-quality footage of fast-moving subjects such as vehicles?
- High resolution sensor
- Wide dynamic range
- High frame rate (30+ fps) (Correct answer)
- Motorized varifocal lens
Correct answer: High frame rate (30+ fps)
A high frame rate minimizes motion blur, ensuring individual frames of fast-moving vehicles are sharp enough for evidentiary use.
Question 7: In a school environment, where should cameras NOT be placed due to privacy regulations?
- Main hallways
- Parking lots
- Restrooms and locker rooms (Correct answer)
- Building entrances
Correct answer: Restrooms and locker rooms
Cameras in restrooms and locker rooms are prohibited by privacy laws and regulations, including FERPA considerations and state statutes.
CST CCTV Camera Selection & Placement 3
What is the primary purpose of a camera's IR cut filter (ICR)?