In this article, we are going to tell you how to effectively use your surveillance camera during the night, including how to use night vision cameras through glass.
From low-cost to high-end surveillance cameras, almost every consumer-grade surveillance system now includes some form of night vision capability. While the quality might differ across the different price points, even cheap cameras are good enough to monitor your backyard during the night—as long as you don’t run into any IR reflection problems.
But before we get started…
Types of night vision
Essentially, there are three different types of night vision: active infrared illumination, image intensification, and thermal vision.
- Active infrared illumination: This is the type of night vision you find on pretty much all consumer-grade security cameras. The device emits an infrared beam towards the target and records the reflected light, converting it into a visible image.
- Image intensification: This is the technology found in devices like night vision goggles. These devices use vacuum tubes to enhance the light hitting the device, and they can intensify natural sources, such as the stars in the night sky, to allow their users to effectively see in the dark.
- Thermal vision: This type of technology detects the temperature difference between background and foreground objects and does not need any source of illumination.
How do infrared cameras work?
CCTV cameras use infrared technology to see in the dark. Most cameras have small infrared LEDs that shoot IR beams that bounce off the target, allowing the reflected light to be captured by the camera itself.
Some cameras only turn on their IR LEDs at night, while others have them on all the time, relying on a filter to bypass the infrared image during the day.
The benefit of using infrared for nighttime capabilities is that it is relatively cheap to do so. However, infrared does have some major drawbacks. Besides it being very easy to spot an infrared beam (even your phone camera can do it), infrared also has a limited range and is prone to IR reflections.
IR reflection: the problem with infrared cameras
The main problem with infrared cameras is that they are prone to IR reflections. Basically, the IR beam itself might be reflected back to the camera, causing the image to have spots, become blurry, or even become unusable.
This problem can be caused by different factors, such as poor camera housing (common in cheaper cameras) or objects too close to the emitted beam. Dust inside the housing and near the IR LEDs can also cause reflections and damage the image.
But it’s glass that is the primary source of IR reflections. Consumers often want to use their indoor CCTV camera to record an outside area and place it near a window. While this can sometimes work, users often misjudge the distance that there should be between the camera and the window. When the camera is too far away from the window, the IR beam bounces from the glass back into the camera, rendering the image unusable.
But how do you use a night vision camera through glass?
How to use a night vision camera through glass windows
Luckily, it is easy to fix most IR glare problems caused by a too-large distance between the camera and the window. You just have to place the camera as close to the window as you can.
If the camera is glued to the glass, the IR beams will not bounce back into the lens, allowing you to record the exterior without any visual aberrations.
However, it might not always be possible to place the camera right next to the glass window. If that’s the case, there are some other fixes you can try. You just need to understand that some of these fixes have drawbacks.
Other fixes for infrared glare
Consider an outdoor CCTV camera
While indoor CCTV cameras are often cheaper than their outdoor counterparts, as we’ve seen, there are times where you might not be able to successfully monitor the exterior of your home.
An outdoor CCTV camera fixes that. By placing a camera outside the house, you are effectively eliminating the obstacle between the beam and the target, reducing the risk of infrared glare.
Install motion-activated lights and disable the IR functions of the camera
If you wish to see nighttime footage but have disabled the infrared functions of your camera, then a motion-activated light source might just do the trick. These lights stay off most of the time unless something (or someone) triggers them.
If that happens, the security camera will be able to record what’s happening, thanks to the light provided by the motion-activated light.
Disable the IR functions
While not all cameras allow you to disable their infrared capabilities, you can always physically block the IR LEDs. If you don’t need to record during the nighttime and are suffering from IR glare on your security camera footage, then consider disabling the LEDs.
You can remove them from the camera or just put some tape over them. The trick is to ensure that there’s no beam that can be reflected towards the lens.
The best way to use night vision cameras through glass windows
Glass will always be a problem when it comes to infrared beams. If you cannot install an exterior CCTV camera, then moving your camera as close to the glass as possible is your best solution to using night vision cameras through glass.
Wrap up
To wrap up our guide on how to use night vision camera through glass windows, low-light situations can be recorded with the use of night vision cameras. They project an infrared beam towards the target using infrared technology, record the reflected light, and then transform the image into visible light.
Active infrared illumination, image intensification, and thermal vision are the three different types of night vision. Infrared cameras frequently experience IR reflection, especially when they are positioned too far from a window. It is advised to position the camera as near to the window as possible to avoid IR reflections if using a night vision camera via glass.
If this is not practicable, additional solutions include adding motion-activated lights, employing an external CCTV camera, or manually turning off the IR lights.
Check out our article on night driving glasses too.