When someone asks for a security system for a villa, the first answer they expect is a number. But the right number doesn't depend on square footage: it depends on access points, meaning the points where you enter and exit. A large villa with only one gate and a back door can be covered with four cameras; a smaller house with four entrances and a garden on three sides requires six or seven.
Start with the access points, not the walls
Walk around the house and mark every point where a person can enter: pedestrian gate, driveway, front door, back door, French door in the living room, external staircase, ground-floor window accessible from a low wall. Each access point needs a camera that captures it clearly, not just in passing.
Then add two context points: one that captures the entire driveway or courtyard, and one that covers the blind side, the one without windows, which is the preferred side for those who do not want to be seen.
Recognizing or noticing: two different jobs
There is a technical difference that explains why a system is sometimes "useless" after a burglary: a camera covering a yard tells you that someone passed by; a camera covering an access point tells you who. To recognize a face, you need about 250 pixels per meter on the subject, and this means keeping the frame tight: two or three meters wide at most at the point where the person passes.
In practice: put cameras with a tight frame at face height on the gate and doors; use a wide-angle lens on the garden and courtyard for an overview. These are two different jobs and a single camera does not do both.
Lenses, in simple terms
A 2.8 mm lens has a wide view (about 100 degrees) and is used for nearby spaces: an entrance, a courtyard, a garage. A 4 mm lens narrows and lengthens the view, and is the right choice for a driveway or a gate ten to fifteen meters away. Beyond twenty meters, or when you need to read a license plate, you need an even longer lens or a motorized camera with zoom.
Heights that work
Between 2.5 and 3 meters is the right range. Any lower, and the camera can be reached and blinded with spray. Any higher, and you are just filming heads and shoulders while faces remain unseen: this is the most common mistake in budget installations—all cameras under the eaves at five meters, resulting in beautiful images but no recognizable faces.
Watch out for the sun as well: a camera facing east in the morning, or west in the evening, will be backlit right during peak passage hours. If you cannot change the direction, choose a model with true WDR, which is the function that handles strong light differences in the same scene.
At night: color or black and white
Infrared cameras see well in the dark, but in black and white: the color of a jacket or a car, which is often the only useful detail, is lost. Cameras with white light illuminators record in color even at night and have an additional deterrent effect, because those who approach see the light turn on. The compromise we recommend most often is a mixed approach: white light at access points, infrared at context points where color matters less and the light might bother the neighbors.
The rest of the system
A video recorder with a surveillance-grade hard drive sized for the number of days you want to store footage, a PoE switch that powers all cameras with some headroom, and an internet connection to view the images from your phone. If the villa is large and the runs exceed one hundred meters, the network must be planned in advance: we discuss this in our guide on distances.
You can find the cameras in the turret and bullet sections, the complete systems in the professional kits, and everything else in IP video surveillance. Send us a satellite photo of the house with the access points marked, and we will tell you how many cameras are needed and where: info@elettricity.com, 351 969 5157.