The lighting on most commercial and public properties does not provide enough ambient light for public safety or for video surveillance cameras to function properly. Ignoring for a moment that poor lighting provides opportunities for criminal activity, video surveillance cameras that cover these areas may not have enough lighting to accurately reproduce the images in the recordings.
Camera Performance
As an example, one manufacturer offers a camera which is capable of recording color video at 0.03 lux or 0.003 foot candles. To put that into perspective 1 foot candle compares to the amount of light a single candle can produce within 1 square foot. While the camera will still record at this light level there isn't enough detail to provide identification and may barely be enough for detection through the software. There is a reason we do not read by candle light anymore, (although, I must say it is relaxing).
The quality of lighting greatly affects the recorded video and the automatic detection of a video management software. It also hampers the ability for humans or the software to identify license plates, car makes or models, individuals, clothing, and other details which may help identifying and prosecuting criminals at a later date.
We do get some help from the cameras though as many modern video surveillance cameras
include infrared (IR) illuminators. Think of it as a flood light that is only visible on the IR spectrum. On some models these are easily identified as the red glowing lights at the front of the camera during night time or low light operation. The infrared light will provide live video and recordings in different shades of grey or green depending on the technology used. Manufacturer’s also make standalone IR illuminators to be used as wide area IR flood lighting for cameras with no built-in IR illuminator or which require a greater coverage.
Problems
IR is a great addition to these cameras, but it’s not always a sole solution to the problem of poor lighting. A major issue this creates is the inability to accurately determine color. As mentioned above the images are either recorded in black and white or shades of green and black. Was the individual wearing a red shirt, or was it navy blue, brown maybe?
The other main issue is that dimmer scenes also lower the level of detail. The greater the amount of light captured by the camera's imager the greater the detail of the scene. Even when the camera is recording under IR the details can be very low quality. Blocky images, distorted faces, numbers and letters too hard to make out.
Solutions
If your goal is to detect movement and send an alarm than the level of lighting isn’t as important, however what is the purpose of the camera if only to send an alarm? The goal should be to record and identify individuals and other details with a reasonable degree of certainty. In the event of a security incident the Security Manager should be able to provide local law enforcement sufficient video evidence and a good still photo for identification purposes. This is also important for creating BOLO’s for employees and security officers to watch for the individual in the future if they happen to trespass or cause additional problems again.
Recommendations
Exterior lighting plays a major part of the security strategy for any business and organization. The right lighting can provide a safe and comfortable walk to the car after pulling a late shift, it also provides the right lighting level for monitoring and recording video surveillance. Whether you are working on a new project or a renovation it is important for your lighting designer to take this into consideration.
Use the Illuminating Engineering Society of North America’s (IESNA) standards for the correct business type and area. IESNA provides recommendations of lighting levels for each area of a business, both interior and exterior spaces. This should be your baseline.
Your security designer should be able to provide some design criteria regarding the cameras minimum lighting intensity level and the field of view which is being covered.
The lighting designer should than select luminaires and perform the initial design calculations.
Once the calculations are completed both the security and lighting designer should review them together and make adjustments as necessary.
It’s important at this stage to also remember any massing which may affect the design calculations. statues, structures, temporary objects such as cars will also affect the light level. Landscaping especially newly planted trees may not be a problem initially, built once full-grown they may cast a shadow affecting the camera's view. Care should be given to nearby light sources which wash out the video and prevent the camera from switching to IR mode.
Conclusion
As you can see there are many factors that affect good lighting and security design. It is important to choose an experienced and qualified security designer for this task. At Bastion Security Group LLC. we understand these issues and can provide a complete review or design for your project to ensure the light levels are sufficient to offer a safe and comfortable area for employees and the public to access. If you need help planning video surveillance or reviewing lighting levels on your project whether a renovation or new construction
Bastion Security Group LLC. is here to help. Give us a call at 1-313-751-8686 or send an email to info@bastionsecuritygroup.com
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