We start with the angle of the lens mounted on specific cameras. Hopefully, you didn’t sleep through that class in school (like I did). The best way to measure the distance is to use trigonometry. There are some calculators available from various manufacturers, but they tend to use the F-number of the lens (mm) rather than the lens angle or are very specific to the manufacturer’s cameras. Well, there are a number of ways to do it. So how do you calculate the distance based on the detail you want to see. Of course you can’t see too much detail at that distance. You can view the moon which is 238,900 miles (384,400 km) away. Someone once asked, how far away can I see with my IP camera? Well, you can see pretty far away. It is also one of the newer IP camera models that provides excellent low light sensitivity and wide dynamic range (WDR).Ĭalculating Distance based on the Camera Lens Angle This is a very nice 2.0 mega-pixel camera with enough resolution to meet these requirements. For example, the Sony SNC-EM630 IP camera has a resolution of 1920 x 1080 pixels. We can now select a camera that has at least 1600 horizontal pixels. (Field of View) x (pixels/ft.) = Horizontal Resolution Use the following formula to calculate the resolution of the IP camera: We can start with the field of view and then calculate the resolution of the camera. We can also do this calculation in reverse. ![]() And, a 10-megapixel camera, with 3648 x 2752 pixel resolution, provides a 45.6 ft. If we have a 5-megapixel camera with a resolution of 2592 x 1944, then the widest horizontal field of view is 32.4 ft. If the camera resolution is 1920 x 1080 pixels (2-megapixel), then our widest field of view is: = Field of Viewįor the following example, let’s assume you would like to identify the face of a person you already know. Total Horizontal Resolution / Pixels per ft. The following formula is used to determine the field of view: How wide a field of view can we see and still be able to identify a person’s face? To calculate the widest field of view, divide the number of horizontal pixels (available from the camera) by the pixels/ft. We consider this higher pixel count to be more of a forensic identification than a personal identification. But, if you need to identify a person you don’t know then you need a lot more resolution. (260 pixels/m) to identify someone you know. ![]() We determined that if there is good light you will require about 80 horizontal pixels/ft. In a previous article, we discussed the resolution required to identify a person’s face. White paper: Video Management Software for IP Camerasĭetermining the Viewing Area or Field of View.Smartphone Door Access Using Bluetooth Reader.Integration of IP Cameras and Door Access Control and more.Analytic and Specialized Camera Systems.
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