Motion detection camera alerts that fire all night: why, and what works better

Motion detection asks one question: did the picture change? It does not ask what changed. So anything that moves or flickers in view counts, and at night there is a lot of it.

You can tune it with a cleaner lens, a smaller detection area, lower sensitivity and a schedule. That helps, but it has limits. A better fix is to alert only on what you care about, which is usually a person or a vehicle, and to check each event a second time before it reaches you.

Motion detection compares one frame of video with the next. If enough of the picture changes, it calls that motion. These are the usual causes.

• Insects and spiders. At night many cameras switch on infrared lighting. Insects and spiders are drawn to it, and one close to the lens looks huge in the picture.
• Rain and snow. They show up as many small moving dots, and infrared light makes them stand out more.
• Headlights and passing light. A beam from a car sweeping across a wall changes the whole picture for a second.
• Shadows and wind. Moving shadows, and trees, bushes, leaves and flags in the wind.
• Sudden changes in brightness, such as a light switching on, which can look like movement to a recorder.

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Menu names differ by brand, model and firmware, so use your recorder's manual. The steps are the same.

• 1. Find the cause. Open five or six false alerts and note the time and what changed first. If they are all at night, think insects, webs and infrared. If they happen in wind or sun, think branches and shadows.
• 2. Clean the lens and housing, and keep webs and insects off them. Trim any branch that sways in front of the camera.
• 3. Draw the detection area. Many cameras and recorders let you mark the part of the picture that counts. Leave out trees, a road, a public path and the sky.
• 4. Lower the sensitivity a little. On a Hikvision camera the scale runs from 0 to 100, and a higher value triggers more readily. Lower it in steps. Too low and you may miss a real person.
• 5. Set a schedule. Use alerts only for the hours you care about, such as after close. On Hikvision, an event only works while its arming schedule is active.
• 6. Use the size and duration filters if your camera has them. Some cameras can ignore small objects, and objects that appear only for a moment, such as a car's headlights or a quick shadow. Axis offers both.
• 7. Try the human and vehicle option if your camera has one. The next section explains it.
• 8. Change one setting at a time. Then walk through the area at night and check you still get an alert.

Plain motion asks, did the picture change? Person and vehicle detection asks, is there a person or a vehicle in view? A moth, a raindrop or a shadow is neither.

• On Hikvision cameras that support it, you set the detection target to Human or Vehicle, and alarms not triggered by a human body or a vehicle are discarded.
• On Dahua, Smart Motion Detection does a similar job. Dahua says it filters pets, insects, extreme weather, branches and leaves. You choose the target (human, vehicle or both) and the sensitivity.
• Not every camera or recorder has this. It is often missing on older models. Check your manual, and switch it on first if you have it.

Person detection built into a camera runs on a small chip inside it, and it can still be wrong. Our software runs on a Windows computer at your site and reads the video from the cameras and recorder you already have. Our own AI models, trained in-house, look for people in the zones and hours you mark, and for smoke and fire. A second, larger model then checks each event before you are alerted.

What reaches you is a photo with the camera and the time, on WhatsApp, Telegram or the Foreman app. The alerts are about a person in a place, not about a change in the picture. No system is perfect, and a camera that cannot see the area at night still cannot see it. Quieter does not mean blind.

Your recorder keeps recording and keeps its own motion recording. You do not have to change it.

Motion recording still has a job. It means the recorder saves video only when something moves, which can save disk. Keep it for that. Use alerts to tell you when something that matters happens. For more, read video analytics: what it is and how to judge it and how to get AI alerts from your existing CCTV cameras.

Our software works with Hikvision, Dahua, CP Plus, TVT, Uniview, Axis, Hanwha, or any camera or recorder that offers RTSP or ONVIF. It installs in 60 seconds and does not change your recorder.

• People in the zones you mark, outside the hours you set, is standard on every site.
• Smoke and fire, a covered camera and a camera that goes offline are standard too.
• Rules in plain words for people, vehicles, zones and times.
• Your recordings stay on site, and we never train on your video.