CCTV: Separating Fact and Fiction
|Copyright 2014 by Virgo Publishing.|
|By: Chester Gilliam|
|Posted on: 06/01/2007|
When I visit with clients about CCTV (closed-circuit television) systems, I become aware of just how influential the movie and television industry is. There are things that are real and things that are not, but sometimes it gets hard to tell which is which.
What we see in the entertainment industry as the norm for CCTV systems is usually just like the shows we watch—total fantasy. I once had a client say, “You know how in the movies they always have the right view of what happened, and how they can zoom in and get whatever details they want, and then spit out a picture showing the whole thing? Well, that’s what I want.” My reply was simple: “Me too.”
The reality is unless you’re making a movie, it’s not going to happen. Where self-storage is concerned, we’re limited in what we can accomplish with cameras.
The first limitation comes from the visual area we’re trying to cover. We’re generally observing a long, narrow area (hallway or driveway). While we can see movement past 150 to 200 feet, we’re hard pressed to determine if the focus is a man or woman, how old they are, or any other characteristics to make a positive or reasonable ID. At anything beyond 200 feet, you’re challenged to identify anything at all.
The second limitation is manpower. We can’t afford the luxury of having someone sit and watch the cameras 24/7/365, looking for that problem area and adjusting the cameras to zoom in and focus on that one spot we need to get a better look.
Third, we have a timing problem. In many cases, we may not know for several days that there was a problem. This compounds the issue of trying to get good information, as we are now relying on recorded images to figure out when and what happened.
Head Out of the Clouds
So what do we do? Give up on cameras? No. But we should take a practical approach to the problem. Camera systems can be a valuable tool if we just use a little common sense when designing and installing them. Each site presents its own unique problems, and it’s easy to under or over design. As with any other security system, if you’re going to do it right, you have to work out a sensible plan and not cut corners.
We’ve said our first challenge is getting a good picture of what we want. When we design a camera system, we first look at placement, which is critical. I try to place cameras so tenants have to pass by as many as possible while going through the site, thus giving a better opportunity for positive recognition. I may not be able to make an ID at the point of the incident, but I want to be able to trace the tenant’s path and make that positive ID at some point.
The advent of keypad cameras has helped in this area, but with all of the different vehicle types, it’s not a cure-all. You should still try to get that ID shot from multiple cameras.
There are several types of cameras available today. Not too long ago, we had black-and-white—that was it. Now we have four basic types, and those have several options. We have black-and-white, color, day-night and infrared (IR) cameras.
Black-and-white provides the best resolution. Color gives our brains more to look at and, therefore, we think it has a better resolution; but the reality is black-and-white is better, especially at night or in low-light situations. Color gives more things to recognize such as clothing and car color, but it loses a great deal of resolution at night or in low light.
This is where the day-night camera steps in and takes us to the next level. In daylight, the camera is color; but at night or in low light, it automatically switches to black-and-white. This gives us the best of both worlds. However, unless we have adequate lighting, we’re still at a disadvantage at night, with our pictures being grainy and pretty much useless.
This brings us to the advent of the IR camera. These are color cameras with a series of small infrared lights that allow them to “see in the dark.” While the range is limited, there are affordable models that can see up to 150 feet in near darkness. This is a vast improvement over where we were just a few years ago.
Another item to consider when looking at camera choices is the number of lines of resolution. The higher the number of lines, the greater the resolution and the better the picture. The lowest number to consider is 380 lines. Something in the 480- to 520- line range will give you substantially better pictures.
All of these cameras come in fixed and pan-tilt-zoom (PTZ) models. A fixed camera is aimed at a certain area when mounted. In other words, you point it at what you want at the time of installation. PTZ cameras have the ability to pan or rotate 360 degrees, tilt up and down and, best of all, zoom in on an object. This allows you to get facial recognition up to 200 feet and farther. The drawback to PTZ is you have to have a person watching the camera and moving it to get the shot you want.
This is another of the challenges we discussed earlier. Fortunately, technology has given us a few ways to get around it. The first is the auto-zoom mode. With this feature, when triggered, a camera will automatically zoom in for a preset number of seconds and then zoom back out to the preset view. The trigger can come from a keypad, alarm point or any number of other standard contact points.
The other totally automated system is CloseView, a product that allows a PTZ camera not only to zoom in on an area, but to actually track an item as it moves. This is done using a series of reference cameras and a specialized camera controller. CloseView takes the place of a person and allows for total automation of the camera system. But like other options, it is limited in use for self-storage and must be planned for and implemented correctly.
Digital Video Recording
If you’re installing a new system or have not yet switched to a digital video recorder (DVR), you have only one choice: Get a digital recorder. DVRs are affordable and feature-packed.
With few exceptions, they all have the ability to be remotely viewed. Backing up or copying what you have recorded is as easy as copying a file to a CD or flash drive. Storage capacity is only limited by the size of your hard drives, thus providing a longer record time.
Searching for events is quick and easy because you don’t have to look through hours of video to get to the few minutes you want to see.
It’s difficult to calculate the number of days of activity you can record with a DVR, but the idea is you have so many cameras being recorded at a certain number of frames per second. The fewer cameras being recorded and the lower number of frames per second, the greater the storage capacity you’ll have.
Digital recorders also allow you to record based on motion-detection, which reduces the amount of information being recorded and the need for greater storage capacity.
When designing a CCTV system, I use the following rule of thumb: For a four-camera system, I use a DVR with a 160 GB (gigabyte) hard drive as a minimum; for an eight-camera system, I use a 360 GB minimum; and for larger systems, I use a 500 GB hard drive. This may vary with the manufacturer and video compression rates, but it’s a good guide to use when trying to decide on the DVR hard-drive size.
Don’t Cut Corners
Your camera system is not the place to cut costs. The old sayings “You get what you pay for” and “Garbage in, garbage out” hold true in this arena. If any part of the system is compromised, the whole system is.
For example, you can’t connect poor-quality cameras to a DVR and expect to get better quality pictures. The same is true for hooking high-quality cameras to a mediocre recorder. If you use a low-grade monitor system, you’ll have bad pictures. The system has to match from the simple items such as power supplies and cables to the cameras, DVR and monitors. While you can enhance the picture using a DVR, you can’t enhance the picture quality, nor can you change what was recorded.
When designing your CCTV system, remember to be realistic in your approach. Choose you camera placements to maximize coverage, use the highest quality components you can afford, and don’t expect the miracle of the movies.
Chester A. Gilliam works for Centennial, Colo.-based Wizard Works Security Systems, which specializes in the design and installation of self-storage security systems. He has been involved with self-storage security systems for the past 20 years. For more information, call 303.798.5337; e-mail email@example.com.