In this article, I look at how security cameras are able to work at night time in complete darkness. These include finding out more about infrared and how the technology is used in security cameras.
And, I focus on just how far these cameras can “see” at night by looking at some of the best selling security cameras on Amazon and comparing their night vision range- the maximum distance that they can record footage clearly.
 What is night vision and how does it work in security cameras?
Modern security cameras often use night vision technology to help with visual detection at night because it allows the camera to see in low-light conditions. Night vision in security cameras is achieved by using any one of these three methods, low-light amplification, thermal imaging and infrared illumination.
 What is infrared and how does it work in night vision?
Night vision can work by three different methods depending on the technology used to construct the camera. All methods, however, rely on the use of IR, sometimes called infrared light which is in a light spectrum that’s not visible to the naked eye. Infrared is a form of electromagnetic radiation and it has wavelengths that are longer than those of visible light. The wavelength of visible light that the human eye can see is very limited in range and generally renders IR invisible to the human eye. Only under very specific conditions and settings can Infrared light be made to be seen by the human eye, however, we can feel it as heat.
One method used for night vision works by using a low-light image enhancement technique. This method can produce great quality images in low-light. Keep in mind that there does still need to be a light source present to produce an image. Typically security cameras using this method tend to be less expensive and are suitable for homeowners because of its ability to identify people. This specific method works by the camera using what is called image intensifiers. These intensifiers, which collect tiny bits of light from the lower end of the infrared light spectrum, work to amplify the light and create a visible image. Camera systems using intensifiers often allows for a broader image view in low-light conditions.
Another method used to create night vision is through thermal imaging, which uses the upper portion of the infrared light spectrum and involves heat. For cameras using this type of system, light is not required in order to produce an image. We have long known that objects radiate infrared energy because of their temperature. This means the warmer something is, the more infrared energy it puts out. When an object is cold and is viewed with thermal imaging, the object will appear black. Vice Versa if the object is hot it will appear white so you’ll only see the images that are captured in black in white. These types of cameras are great for being able to detect objects at great distances. This is due to the fact that cameras offering thermal imaging normally have pretty high levels of thermal sensitivity.
A third method that works for night vision is by using infrared illumination. The camera system combines both IR illumination with motion detection capabilities which creates a highly effective security camera. Another popular camera for homeowners, this camera works by first detecting movement within its field of view. Infrared illuminators are then activated and light up the area so the camera can capture the images. These cameras, similar to thermal imaging cameras, do not require ambient light sources to capture images. Because infrared illumination works by using multiple LED lights these cameras can capture very detailed images including numbers and letters. These camera systems are an excellent choice for home security.
 How far can a security camera see at night?
The distance that you can see on a security camera at night or when it’s dark all depends on a number of factors like resolution, location, focal length, and camera quality.
The most important factor in determining how far a security camera can see is the size of the camera lens or the focal length. The focal length is usually measured in millimeters and the smaller the length the wider the field of view.
The resolution is probably the next most important factor because this will determine the clarity of your images and video content. With resolution, the higher the resolution, the more clearly your images and video will be.
Location is important especially for wireless security systems. The fewer things like walls, doors, or trees between the camera and the wifi signal, the better the quality of transmitted images.
Finally, consider the quality of the security camera that you’re using. When it comes to technology, you often get what you pay for in terms of the quality so keep this in mind when researching security cameras.
[4a] What is the night vision range of some of the most popular indoor security cameras?
When it comes to indoor security cameras not all offer the same level of night vision range. Consider these four top selling cameras as an example.
Amazon offers a security camera called the Amazon Cloud Cam. The range of infrared vision offered by the Amazon Cloud Cam is 30 feet and is the largest range of the four indoor cameras.
Next you have the Wyze Indoor Wireless Camera which offers similarly some of the best visual range of night vision with a range of up to 29.6 feet.
Nest offers a popular security camera that has a night vision range of about 20 feet.
Finally, The YI 1080p Home camera has a bit of a smaller range of about 5 meters or 16 feet.
[4a] What is the night vision range of some of the most popular outdoor security cameras?
Outdoor cameras used for security tend to offer a larger range of distance for IR.
The YI Waterproof Surveillance Detection Camera has one of the farthest ranges available on the market, with a range of up to 50 feet.
Reolink offers an outdoor security camera that features a wire-free rechargeable-battery that comes with a solar panel for recharging. The night vision range on this camera is an impressive 33 feet.
Ring has a security camera that allows you to customize how far you want the range of the night vision to register detection of up to 30 feet. Another top selling security camera called the Arlo Pro.
And the Arlo Pro has the shortest range of the top four cameras with a range of only 23 feet, which is still not terrible.
 Can a security camera see at night without infrared?
Infrared works by using a spectrum of light that we don’t see in order to amplify and make low light imagery more visible.
If a camera does not have IR capabilities you will not see clear images at night or in low light conditions.
 Why do most security cameras have a red glow at night?
On some security cameras you can see a red glow at night coming from the camera. Typically it is one of two things. Either it is just a power light to show that there is power to the camera. However, more often you will find that it is more than one light and it this case the lights are IR lights. 850nm wavelength IR lights are commonly found near the lens of the camera forming a circle around it. These are used to flood the area the camera is pointed at with infrared light for better visibility.
 How can I make CCTV better at night?
There are a number of ways that you can improve the quality of imagery and video from CCTV cameras at night or low-light conditions.
Adding additional visible lighting is one of the easiest ways to boost image quality and brighten up the surrounding area. Having good lighting can even allow your security camera to be able to capture images in color. You’ll want to make sure the lights are bright enough and placed properly to evenly illuminate the desired area. Small porch lights may provide enough light for some small areas, however, a more powerful light mounted high on a pole or building would work even better. If you choose to add more visible lights make sure that you have the lights mounted high enough to reduce the number and size of any shadows.
In the chance that you don’t want to or can’t use bright lighting to illuminate the area, you can also consider adding additional external infrared illuminators. IR illuminators work to brighten up an area using infrared light without having to use bright visible lights. While a lot of cameras come with these, they usually are not strong enough the light up the entire area. Ultimately by providing more infrared lighting, the area will be better lit for the night vision camera to work and the better your images will be.
Being sure to keep light sources out of the view of the camera is another way to ensure good image quality. Having a light source located to close to the security camera or its field of view can causes issues for the camera itself. Lighting that is too close or reflected towards the camera can interfere with the camera’s day/night sensor resulting in very poor image quality. If you have to have a light in close proximity of the camera try to position the light either to the side or behind. The problem of having light directed at the camera lens is that the camera’s image sensor can not process the extreme bight light and the dark areas very well. Many headaches and image quality issues can be avoided by simply remembering this tip.
Similarly to keeping light from being directed at the camera, eliminating reflected IR is another way that you will improve your image quality. IR like visible light will bounce off reflective surfaces and effectively blind the camera with the IR light. IR can be reflected back to the camera from a nearby wall or even a window that the camera sits behind. For windows, one way you can fix this problem is by slightly angling the camera so it’s not aimed straight on towards the glass. Sometimes just moving the camera closer to the window can fix the problem.
Another way to increase the quality of images and video is by selecting a camera that uses Smart IR. Selecting a security camera with the Smart IR feature will help to reduce to chance of your video or photos from getting whited out when objects are too close to the IR lights on a camera. If your camera doesn’t have the Smart IR feature another option to just turn off the cameras built-in IR. Although the infrared lights may help in some cases they may actually work against producing quality images. Because the IR LEDs form a ring around the lens there are times where sometimes the IR light can reach the lens. Due to this, it’s a great idea to turn them off and use external IR illuminators in its place.
 What is Smart IR?
In order for security cameras with night vision to work properly, they rely on infrared lighting. Although infrared lighting can not be seen with the naked eye, it will interfere with your images if they are in color. To help correct this issue most cameras come with some type of an IR cut-off filter or more recently a Smart IR feature. This filter works by sitting between a filter and the camera lens and only allowing IR light during the night time or low-light conditions. For cameras that have this feature, the camera automatically adjusts the intensity of its infrared LEDs depending on the distance of an object. This way the camera can give the field of view consistent illumination and if an object is too close to the camera lens the infrared will not overexpose the object.
 Is there color night vision?
Almost all security cameras are able to capture images in color at night, however, in order to do so, you may need to adjust certain camera settings. You can do this but it is not the best way.
There are now cameras available that use advanced starlight image sensors. How these advanced sensors work is by collecting and absorbing as much visible light as possible. By collecting such a large amount of light, the camera is able to continue capturing color images.
Since normal security cameras don’t have larger enough sensors to collect enough light, they have to rely on black and white images. On advanced color night vision cameras, they typically come with larger size advanced sensors when compared to normal security camera systems.
Advanced color security cameras also have a wider aperture, and a reduced shutter speed which helps to ensure enough light is collected. This goes for even when there is not enough light for the naked eye to see.
The one thing to remember about color night vision is that it relies on ample ambient light, such as a porch or street light in order to produce color night vision.