Main > Household > Security
A cheap security alarm can be easily made with a 12 volt motion detector connected to a 12 volt siren. Turn this on when you are out of your house for any extended period of time, and if movement is detected inside your house the siren will go off. These items are cheaply available online.
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Main > Household > Security > Security cameras, IP cameras
IR Illuminators (Infra-red illuminators are a must-have for outdoor cameras. These illuminators should be positioned a least a couple of feet away from the camera, so that the camera doesn't become falsely triggered by raindrops or insects flying into the IR beam. Some of the more expensive illuminators have either a wide beam or a narrow beam to match the field of view of the camera.
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Main > Household > Security > Security cameras, IP cameras
Picture Resolution. The higher the resolution the better, but be aware that the higher the resolution, and the higher the frame rate you use, the larger the files will be, the slower the transfer times, and the more image processing work will be necessary. 720p has only 45% of the number of pixels compared to 1080p, and 960p has only 59% of the number of pixels compared to 1080p.
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Main > Household > Security > Security cameras, IP cameras
Lens type and focal length will determine how wide the angle of the view will be. Wide angle lenses, like 2.8mm or 3.6mm, will show a large scene, but may not be able to capture details like faces or number plates at a distance. Telephoto lenses such as 8mm or 12mm will show a magnified, but a narrower view. Ideally you can use both wide and narrow angle cameras. For example, a wide angle lens will capture an entire car park, and a narrow lens can capture the car number plates at the entrance/exit to the car park. If you have a number of cameras around your house you may be able to place one camera, with say an 8mm or 12mm lens, in a position which can see all passing traffic, and which magnifies enough to see faces and number plates.
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Main > Household > Security > Security cameras, IP cameras
Wifi or Wired? Wifi is okay for indoor cameras, but for outdoor cameras you will have a much more reliable experience by using ethernet wiring, especially with "Power over ethernet", where power is sent along the one ethernet cable with the data.
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Main > Household > Security > Security cameras, IP cameras
Fake or Dummy cameras. If you have an old security camera that doesn't work any more, or is technologically obsolete, you can put it up somewhere you don't have a working camera, to act as a deterrent. Cameras are a big deterrent to burglars.
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Main > Household > Security > Security cameras, IP cameras
Where to position security cameras? Most burglars enter through either the front or the back door, or through an off-street window where they won't be seen from the street. So these should be covered.
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Main > Household > Security > Security cameras, IP cameras
Night-time light sensitivity is most important, especially if you don't want to use powerful infra-red illuminators. Look in the specifications of the camera for a light sensitivity sensitivity of around 0.0001 Lux at an aperture of F1.2.
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Main > Household > Security > Security cameras, IP cameras
Power over ethernet: If it is difficult to supply power to a camera or access point, you can transmit power over the ethernet cable. Be aware that there may be some speed loss in data transfer, since the power uses some of the capacity of the cable. There are two types of POE: active and passive. The safer and more expensive of the two is "active", since there is a negotiation between the sender of power and the receiver. The "passive" type of POE simply assumes there is no problem with the power supply, which is risky. At the upstream end, power is injected into the ethernet cable. An active POE injector will normally inject 48v. At the downstream end this power will need to be dealt with. If the downstream device is an active POE device, it will deal with the power. However, if it is a passive POE device, it will expect the correct amount of power to be delivered to it through the ethernet cable (e.g, 12v, if it is a 12v device). In the case of a non-POE downstream device, a POE splitter will be required to split the power and the data from the ethernet cable, for use by the device. Splitters can be active (intelligent) or passive.
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Main > Household > Security > Security cameras, IP cameras
Seeing through Windows can be a problem for IP cameras because the IR lights will reflect back off the glass and make it impossible to see anything through the glass at night time. If your camera software does not allow you to turn off your IR lights, you can open up your camera and manually remove the cable supplying power to the IR lights. It is normally the larger of the connections leading to the board containing the IR lights. Then, if you can, change your camera options from "IR Synchronous switch" to "Automatically switch", to make sure the camera switches to black and white when it gets dark, independently of the IR lights. You should then install external IR illuminators, outside of the window. Note that room lights from within the room should be turned off, otherwise you may see reflections from inside the window.
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Main > Household > Security > Security cameras, IP cameras
Convert wired IP cameras to Wireless (Wifi). This is possible through the use of a dedicated wireless bridge unit, or through a wireless access point. The access point should have enough network ports on the back for the number of cameras you want to plug into it, and should be wirelessly connected to your wireless network either in Bridge mode or in Repeater mode. Remember to elevate the access point for better transmission and reception. Also, if the unit has more than one antenna, don't have them parallel.
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Main > Household > Security > Security cameras, IP cameras
Images from cameras appears too dark during the daytime. This can be caused by having too much of the sky in the picture. The camera adjusts its exposure based on the sky, and darkens the picture. If you angle your cameras downwards, including less sky, the pictures will become brighter. This is especially important for cameras that have wide-angle lenses, since they tend to include more of the sky.
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