With all of the marketing that’s out there about security cameras, it’s tough to wade through and figure out what camera fits your application. The problem is exacerbated by manufacturers providing widely varying amounts of information for you to assess the quality of a camera and testing it in various conditions.

Hopefully, we can make determining a starting point for your camera system’s resolution a lot faster.

How much resolution do I need for a home camera system?

Fill out the form below, and see what the minimum resolution to meet your requirements will be.  If you’re not sure about what to use, we list cameras and viewing angles at our home surveillance camera comparison page.

Find camera information here!

Assumptions

You should know that the calculation above has several assumptions inherent in it.

  1. We use resolution recommendations used by the FBI and advocated by several camera companies of 80 pixels per foot.
  2. Recognizing a known person will take about half the resolution of recognizing a stranger.  We used the more difficult standard and assume that you’ll most often want to ID strangers.
  3. To calculate viewing angles, we assume a 16×9 camera format common in new cameras rather than requiring you to figure out which camera format you’ll use ahead of time or adding complexity to the recommendation process to support legacy equipment.
  4. The calculation assumes that the arc length of camera coverage closely approximates a straight line.  Or in other words, we assume the distance to the object is large enough to make error due to that assumption negligible as it is in most applications.
  5. The calculation does not take into account the angle of the subject relative to the camera which could make identification more difficult (side views or looking down).

Other Caveats

The recommended resolution will be a good choice in good lighting with no resolution degradation from poor electronics in the camera or low lens quality.  There are many factors beyond the resolution produced by the image sensor in a camera that determine the quality of images produced by the camera.  Keep in mind that this recommendation is a starting point.

Method

The calculation itself is pretty straightforward.  We use geometry to compute the size of the image at the given distance, and then apply the resolution requirement that you selected to that image size to compute the required resolution.  From there, we recommend the next highest common home camera system resolution size to insure adequate image quality.

If we saved you some time, pay it forward by telling others! Here’s a suggested message:

I saved a lot of time choosing my home security camera using the resolution calculator at http://24-7-home-security.com/home-camera-system-resolution-calculator/.  Check it out!

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