Explaining Security Camera Specs

by Deep Sentinel | | Learning Center

The technical specs on a home security camera tend to be confusing. In this article, we’ll clarify some complicated camera specs, and describe which ones are the most important to consider. This ought to help you find the best option that suits your home security needs.

Field of View

The security camera’s field of view is very important to consider. It is how far to the left and right, up and down, that the camera is able to capture. If you hold your arms straight out to the sides, you can most likely see them. That’s a 180-degree horizontal field of view. The human field of view is roughly 210 degrees horizontal, and 150 degrees vertical. Security cameras have a narrower field of view, but unlike the human eye, maintain their focus all the way to the edges.

Security camera specs don’t normally list the camera’s horizontal and vertical field of views, however. They list the camera’s diagonal field of view, which will be a bigger number. It’s a complex math equation to go between the three, so just realize that a security camera touting a 145-degree field of view can see horizontally slightly less, and vertically much less. The reason for vertical view being much less is due to the common recording shape of camera sensors, which is much longer than wider.

Pay special attention to each security camera model’s field of view, because it ranges widely. The greater the field of view, the more your camera sees around it, which is integral for avoiding blind spots. Having a wider field of view also reduces the need to painstakingly position your camera, because it again will capture more of what’s around it than a security camera with a smaller field of view.

720p vs. 1080p Video

With all security cameras, there are two important and competing factors: high detail, so that the video can capture faces and other critical details, and low enough data usage to be able to send this constant data over your internet and reduce the processing needs of the camera.

720p records 720 pixels of information from top to bottom, and 1280 pixels of information left to right. Overall, it’s roughly a 0.9 megapixel camera. That may seem like a very low resolution, but security cameras must take about 30 pictures per second, so a 720p camera is dealing with about 27 megapixels of data every second. Security cameras have their ways of internally reducing the size of the data that has to be sent out while maintaining image quality, but that requires a lot of processing power.

That is all to say that 1080p requires more processing power and larger data packets to be sent out. This mean a couple of things. First, if they are battery powered, cameras that record 1080p will chew through batteries quicker than similar cameras running on 720p. Second, they will use up more of your internet for transferring if they are wireless. Most wireless security cameras get around these two drawbacks by not recording all the time, and only record when their sensors detect sound or movement.

The benefit of having 1080p, which is 1920 pixels wide by 1080 pixels tall, is higher detail. It is slightly more than twice the resolution of 720p, at just over 2 megapixels. This might be the extra detail you need to read a license plate or to make out the face of a burglar. Realize, however, that if this is a wireless camera, you will need a good WiFi connection to actually get a good resolution video out the other end.

HD Video

The only reason this is a separate category is because of the confusion around it. HD stands for High Definition, and means it has at least 1280 pixels by 720 pixels being recorded. This is the same as 720p, but it sounds much better when listed as HD, so expect many markets to advertise it as such. 1080p is also HD, but expect it to be stated openly as 1080p because it sounds better.

Night Vision

The last spec we will look at in this article is night vision features. All home security cameras equipped with night vision use infrared (IR) LEDs to see at night. Always check the specs for the distance of the night vision, there will be a certain point beyond which everything is black. The more IR LEDs, the brighter it will bathe the space in front of the camera with infrared light, and the better the image it can produce at night.

Although most burglaries take place during 10am and 3pm, having a night vision capable camera will make the security camera actually relevant at night for capturing criminal activity. Otherwise, you will have to keep plenty of lights on at night to prevent night-visionless cameras from creating noisy or blurry images with not much detail.

An IR cutoff filter is used by security cameras to automatically turn off the IR LEDs when there’s enough daylight. This prevents the infrared from distorting the video quality during the day when it is counterproductive.

For More

This article was dedicated to technical specs specific to the camera part of a security cameras. Some security cameras have a lot of extra features that do not relate to their video abilities, which is a whole other can of worms.