Selecting the lens for your IP Camera

How to Select the Lens
Go to each location you want to view with your surveillance cameras. Bring your digital camera to each of the locations. If you don't have a digital camera this is a good excuse to get one. The camera should have a zoom lens that has mm markings on the lens so you can record the right mm for the lens.

Again, decide where you would like to place the camera. Place the digital camera as close as you can to the planned location of the video camera. Take a picture of the view you would like. This is will define your field of view. Record the lens position (so you can later select a similar mm lens). Measure how far away the camera is from the field of view at each location. Record how wide an area you would like to view. This should be determined by the picture you took using the digital camera. The distance to the area and the width of the area define the lens. You can use the lens calculator at http://www.kintronics.com/iqinvision/lenscalculator.htm to determine the lens mm.

If you decided that you need a PTZ camera, you can still use the lens calculator to determine if the zoom lens is within the range you need. For example some cameras have a 10X zoom (4.2 – 42mm) and some have over 22X (3.9 – 85.4mm). Use the lens calculator to see if the area you want to see fits in the range of the camera you select.

You can find a lot more information about cameras and lenses at the kintronics web site

How to select the right IP camera

How to select the type of camera
Should you get a fixed position camera or a Pan, Tilt, Zoom (PTZ) camera? Go to each of the locations where you would like to install a camera and take a look at the area you would like to view.

Now let’s see what the camera will see. This is where your digital camera can be helpful. Hopefully you have one, but if not, this is a good excuse to get one. Decide on where you would like to place the camera, for example on a building or on a light pole, etc. Try and approximate the location of the video camera and then use your digital camera to view the area you want to view.

If you have to move the camera right and left to see everything, then you probably need a Pan, Tilt, Zoom (PTZ). If you have to move the camera only a short distance then maybe you can use a high resolution camera with a wide angle lens. If you can see everything with the camera in one position then a fixed camera will work.

Selecting the right resolution for your IP camera

So you have decided to install a surveillance system at your site. It may have been that the bad guys are breaking into cars in the parking lot or someone is helping themselves to equipment or products in the warehouse – for whatever reason you need to see what’s happening. Now what do you do next? How do you determine exactly what you need? It’s time to do the site survey. Here’s what you do:


How to Select the Resolution you will need
The resolution defines the detail that you will see. I have talked to a number of people who have video surveillance camera systems and find that the video that they stored is not clear enough to make out a person’s face. This is because they don’t have enough resolution. Now resolution is not only determined by the camera so be careful here. Sometimes you may get a good resolution camera, but then the resolution is lost when it’s stored in the recorder. A typical problem is that video is compressed so you can store many days in the recorder. Compression increases the amount of video you can store but decreases the resolution.

Resolution is important if you are trying to view a person’s face (or a license plate number) in a large area. This is especially true if the object you are trying to view takes up a small part of the overall picture. The wider the area you want to view the more resolution you need to see all the detail.

There was a study done by the US government that determined that you need 50 pixels per foot to identify a person’s face or read a license plate number. So if you have a 700 x 480 pixel camera it can view an area that is 14 feet wide (700 pixels/50 = 14). If you want to view a larger area, you need more pixels (higher resolution). A camera with a resolution of 1600 x 1200 can view an area that's about 32 feet wide. Take a look at http://www.kintronics.com/iqinvision/IQe3spec.htm for examples of high resolution IP cameras.

NVR software manages the IP cameras

Why do I need software with my IP camera? All I need is a web browser to view IP network cameras on my PC. I can even control a PTZ camera. Well yes, but surveillance usually requires more than just real-time viewing, you also need to store the video, view multiple cameras, be notified about alarms, etc.

IP video software is the glue that holds a surveillance system together. It displays all your cameras, stores the video and provides real surveillance functions. It makes it easy to view a specific camera, to find the stored video by camera, data and time, and does many other things. There are many choices of IP software available. The one that is best depends not only on what you need to do, but also reliability (it doesn’t crash), usability (it’s easy to use) and efficiency (it doesn’t require many computers to work). There are a number of different types of software available. We have tried a number of them and I can tell you that reliability is probably the most important feature. If it crashes at the wrong time you can lose all that important video. Take a look at Video management software for software that survived our testing.

IP network cameras, in conjunction with IP software systems, can offer much more than CCTV solutions. IP Network video solutions also have advantages over PC-based Web cams. Some of the benefits are briefly outlined below.
Image quality: Image quality is one of the key aspects of IP network video products. IP cameras provide much greater resolution than the analog CCTV cameras. For example, the Hanwha (Samsung) QNV-7084R camera has a 4-Mega pixel sensor and provides a resolution of 2592 x 1520 pixels.

There is also a choice of compression schemes used. For example, Hanwha provides a range of video compression standards (Motion JPEG, H.264 & H.265) for users to choose from. In many network video products, both Motion JPEG and H.264 are supported simultaneously. This enables you, for example, to view at full frame rate with M-JPEG and record at the same time with H.264, allowing for optimization in image quality and bandwidth. Read more on How to Calculate What You Can See. 

IP Cameras are Great

The video surveillance industry has changed a lot over the last few years. I know because I've been around for few years. I actually started out life as an engineer and developed some of the first digitized video systems. This was back in those historic days of 1970's. We used CCTV cameras with vidicon sensors, analog to digital converters, and digital logic (no computers) to detect motion. What fun!

In the last 5 years I have gotten more involved in network attached camera systems or IP camera systems. This is quite a change from those old CCTV analog surveillance systems. Actually they are still around. Why have IP cameras become so popular? It’s because of the improved flexibility and ease of installation provided by this new technology. More importantly, it’s more cost effective. The latest IP solutions even include intelligent video processing that can track objects. Nowadays I don't have to worry about the hardware; it's all software now.

These network attached video solutions enable us to remotely and cost-effectively monitor and secure people, property and industrial processes. You can even use it to conduct remote classes, establish remote troubleshooting sessions, or broadcast sights and sounds on a Web site. Your network video system can be as simple or as sophisticated as you want it to be.

One of the major differences between the older CCTV surveillance systems and the new IP systems is the distance between camera and monitoring station and the ease of access to the video. Analog systems are restricted by the coax cabling systems, IP cameras are as boundless as the Internet.

More about this later. If you have any questions or like to add to this commentary you can contact me at bobmesnik at yahoo . com.