Somebody has broken into your property. You call the police, and fairly early in that conversation they ask whether you have cameras. If you can say yes, it feels like the good part of a bad morning. Then the follow-up questions start. Was a camera pointed at that part of the property? Was there enough light at that hour to see a face? Was the person close enough to the lens? How long does your system hold footage? Most people find out they don’t know the answers all at once, on a terrible morning, after years of believing this was handled. Owning a camera and owning usable footage are two different things, and the gap between them is where this episode lives. Host Mackenzie goes through what the research says a camera is worth after a crime, the failures that turn a recording into nothing, and an afternoon of fixes that require no new equipment. We sell security cameras, so you can expect us to argue that one is worth having. We think the evidence supports that. We also think almost everything that would improve yours costs nothing. In this episode: The one study that measured this properly, covering 251,195 crimes on the British railway network, where footage existed in 45% of cases and was judged useful in 29%What happened where useful footage existed, and why the picture for theft without it is as bleak as it isWhy we are not handing you a figure from a British railway network and letting you assume it describes your driveway, including what the author himself says about private homesDeterrence and evidence are two different jobs, and a camera positioned well for one is usually positioned badly for the otherThe benefits that never appear in any crime statistic and are the ones households actually use, including the disputed insurance claim and the noise at 2 a.m.Why a camera is quite often a device for finding out that nothing happened, and why that is worth saying out loudThe five failures that separate footage that exists from footage that works: direction, distance combined with width, light in both directions, an uncertain time window, and retentionWhy the instinct to fit as much of your property into the shot as possible is the instinct that ruins the recording, and why small is the one problem that cannot be fixed afterwardThe failure that did not come from the study but shows up constantly in home systems, where motion-triggered recording starts a second or two into the eventThe retention arithmetic nobody does before a holiday, when a system holds seven days, and you were gone for 10Why most camera owners have never watched their own footage under the conditions that actually matter, and the free test that takes about 15 minutes tonightThe walk test, and the gap between whether you can see somebody and whether an officer can describe what they were wearingThe clock on your recorder, the detection zone that ignores the pavement and therefore ignores the person walking up it, and the export function nobody finds until somebody asks for a fileWhy roof-level mounting gives you the tops of heads, and the height that gives you facesWhat to do the same day something happens, before the week between reporting it and anybody asking to see itThen the part camera marketing works hardest to obscure. There are three different things a camera can do, and they are not the same job. Seeing that somebody is there works at almost any distance, and almost any camera can manage it. Recognizing, where you can tell an adult from a child or make out a light jacket, needs closer. Identifying, meaning a face somebody could match or a plate somebody could read, needs dramatically closer than most people expect. The measurement underneath all three is not megapixels. It is how many pixels fall on the subject, which depends on resolution, the width of the scene the camera covers, and how far away the person is. Which is why the number on the box tells you almost nothing by itself. A high-resolution camera aimed wide at a distance can put fewer pixels on a face than a modest camera watching a doorway. There is an international standard that defines these categories and the pixel density each one requires, and professional installers design to it. None of it is proprietary. It is just not in the advertising, because the advertising would rather say 4K. Some homes have four cameras all doing the first job and nothing doing the third, and that is the configuration everybody describes afterward as useless. Source named in this episode: Matthew Ashby, “The Value of CCTV Surveillance Cameras as an Investigative Tool,” European Journal on Criminal Policy and Research, 2017. Home & Safe is from Deluxe CCTV — the practical side of keeping a home, and the people in it, safe. deluxecctv.com