It doesn't matter if the light is visible, from the built-in IR, or from an external IR illuminator. Then you are pretty much guaranteed to blind the camera with reflected infrared light. Just like with the visible light in the section above, that surface reflecting the IR light back at the camera doesn't even have to be in view of the lens and image sensor to cause problems.Īlso, just like with visible light, the worst case is when the nearby building surface or another object is reflecting IR light back at the camera and is in view of the lens and image sensor. One common cause is the infrared light from the camera's built-in IR LEDs reflecting off of a nearby surface like the wall or soffit around where the camera is mounted. Suppose you mount a camera on a building and get it pointed where you want, and you find that the daytime image is great but the night time image seems bright enough but you can't really make anything out in the darker areas. This is easier to do than you might think and it can affect the night image of many cameras without the owner even realizing that it is happening. You can also sabotage the ability of your camera to see in low light conditions if you allow extra unwanted infrared light to fall on the front of the camera. You might be able to guess what I'm going to say here if you understood the importance of the last section. Here I am shining a SureFire G3 Nitrolon Flashlight towards these cameras, not even directly into the camera lens, but it is a very bright light. You'll even see some people on the Internet recommending this as a method to temporarily disable security cameras. Here are some extreme examples of what a bright light can do when allowed to be in view of a security camera. Preventing extra light like this from skewing the dynamic range of the image sensor is one of the most important things to keep in mind, and it's an easy thing to accidentally get wrong if you're not careful. If you make it view a bright light it will no longer be able to see very well in the darker areas of the rest of the image. The image sensor may be able to handle a bright image and a dim image, but it can't do both extremes at once. The worst case happens when you want to view an image in low light, and you also have a bright light in direct view of the camera lens. If you must place a camera near a bright light you should try to keep the light to the side and rear of the camera so the light doesn't directly hit the front at all if possible. Whether it's light directly from the bulb or first reflected off of a nearby surface, it all has the same effect on the camera. It could cause the day / night light sensor to not function correctly, and bright light hitting the class over the camera lens can many times get enough light to the image sensor to make it see poorly. Do not place the front of the camera near a bright light, and never allow a bright light to be directly in the camera's field of view.Ī nearby bright light can cause problems even if it doesn't appear in the image viewed by the camera. For a larger wide angle model, see my review of the CMVision CM-IRP12-850.īe aware of all of the light fixtures around the location where you will be installing a camera. For a smaller model with a narrower beam, see my review of the Univivi U06R. I am using several different models of external IR illuminators. Wide angle or narrow beam, weaker for short range or stronger for long range, there are many different configurations available to suit pretty much any application that you can think of. Keep reading to see why.Īdding one or more external infrared illuminators is an ideal way to light up an area without using bright visible lights, and if done correctly can give you an awesome camera image in what appears to be complete darkness to the human eye.ĭepending on the particular models that you choose to use, the price can range from very inexpensive for smaller consumer models to relatively expensive for larger commercial models. Of course some cameras including many high end ones don't include IR lighting at all, but there's a reason for that. Unfortunately, many of these built-in lights don't provide even coverage and most aren't strong enough to illuminate anything at a reasonable distance. Many cameras come with built-in infrared LEDs that light up the area directly in front of the camera allowing it to see in complete darkness. There are many places around the house where people want coverage from a security camera but they don't want a bright visible light turned on all night.
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