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What lens is used in CCTV?

When it comes to surveillance systems, the CCTV lens is the unsung hero that determines image clarity, field of view, and low-light performance. Whether you’re securing a retail store, warehouse, or residential property, selecting the right CCTV lens is critical for capturing actionable footage.

*What Is a CCTV Lens?
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A CCTV lens is an optical component mounted on security cameras to focus light onto the image sensor. Unlike standard camera lenses, CCTV lenses are engineered for durability, often featuring weather-resistant coatings and compact designs to fit discreetly into surveillance setups. Their primary goal is to provide sharp, distortion-free images across varying lighting conditions and distances.

*5 Common CCTV Lens Types and Their Uses
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Fixed Focal Length (Monofocal) Lens

  • Best for: Static surveillance areas like entrances or parking lots.
  • Features: A single focal length (e.g., 3.6mm, 8mm) offers a fixed field of view. Wider lenses (lower mm) capture broader areas, while narrower lenses (higher mm) zoom in for detail.
  • Example: A 2.8mm lens covers a 90° angle, ideal for small rooms.

Varifocal Lens

  • Best for: Flexible monitoring needs, such as adjustable coverage in retail aisles.
  • Features: Manual or motorized zoom (e.g., 2.8–12mm) lets users adjust the field of view without swapping lenses.
  • Pro tip: Motorized varifocal lenses enable remote adjustments via security software.

Fisheye Lens

  • Best for: 360° panoramic surveillance in open spaces like lobbies or warehouses.
  • Features: Ultra-wide angles (180–360°) with heavy distortion, corrected by software to produce a seamless view.
  • Limitation: Objects near the edges may appear stretched.

Telephoto Lens

  • Best for: Long-distance monitoring, such as perimeter fences or highways.
  • Features: High focal lengths (50mm+) magnify distant objects but narrow the field of view.
  • Example: A 100mm lens can identify license plates from 100 feet away.

IR-Corrected Lens

  • Best for: 24/7 surveillance with infrared (IR) night vision.
  • Features: Special coatings minimize focus shift when switching between day (color) and night (black-and-white) modes, ensuring sharp images in total darkness.

*Key Factors to Consider When Choosing a CCTV Lens
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  • Resolution Compatibility: Ensure the lens supports your camera’s megapixel rating (e.g., 4K lenses for high-resolution cameras).
  • Aperture Size: A wider aperture (lower f-number, e.g., f/1.2) improves low-light performance but may cost more.
  • Mount Type: Verify compatibility with your camera’s lens mount (e.g., CS-mount or C-mount). Recommended Reading: Low distortion CCTV lenses

Conclusion

The right CCTV lens transforms (blurry) footage into evidence-grade visuals. Fixed focal lenses offer simplicity, varifocal lenses provide adaptability, and specialized options like fisheye or telephoto lenses address niche surveillance needs. By matching your lens choice to the environment, lighting, and desired coverage, you can build a security system that delivers uncompromising reliability.

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