Trail or game cameras are remote cameras that seem to be in an electronic sleep but become activated once their motion sensors detect movement; their shutters are triggered to capture images or record videos of targets. One of these functions as seen on trail cameras is the PIR mode. What is PIR mode on a trail camera?
PIR mode is a feature that when activated on the trail camera takes a photo only when the PIR sensor is activated. As the name implies; passive infrared sensors detect the motion of objects in its line of view by measuring the infrared light emitted by or reflecting from these objects.
Time and again we’ve heard of motion sensors, a somewhat new feature of most security cameras that detect the movement of people, animals, and objects in its sight that when triggered, captures and sends the image to the owner alerting them of a possible intrusion. In the course of this article, we’ll be looking extensively at the PIR mode of the trail camera. So let’s delve in!
The PIR sensor is an electronic sensor that measures the light or heat emanating from an object, person, or animal in its line of sight. The PIR mode on a trail camera with the help of the PIR sensors detects movement in general but it does not give the information of what or who moved past its line of sight, unless when triggered and snapshots are taken.
The PIR mode is sometimes referred to as a PID, a passive infrared detector. Passive here refers to the fact that the PIR sensor does not radiate energy to detect an object or a person. The sensor works by detecting radiant heat generated by or reflected from objects. Every object with a temperature that is above absolute zero emanates heat in the form of radiation. Normally, this radiation is not visible to our eyes as humans because it’s in the infrared wavelength. This radiation can be, however, detected by electronic devices such as the PID, passive infrared detector which is a part of the PIR mode.
PIR sensors can detect a change in the amount of infrared radiation interfering with it. However, this varies depending on the temperature and surface properties of the object in front of the PIR sensor. When a person, for instance, passes in front of the camera sensor when the PIR mode is activated, the temperature at that point in the sensor’s line of view will increase or reduce from the original temperature of its environment to body temperature, and then back again. The PIR sensor transforms the change in the infrared radiation above into a change in the final output voltage, and this signals the detection.
Objects or animals with temperatures that are similar but have different surface qualities might have an infrared-emitting pattern different from that stated above, thus their movement concerning the environment may also trigger the sensor of the PIR mode to capture images in its sight.
PIR sensors come in different settings for a wide variety of uses. Some of the most popular models possess numerous Fresnel lenses or mirror segments with an effective range of about 12 meters, 35 feet, and an aerial view of less than 180. Some models have wider aerial views up to 360°, though rare, they are designed to be mounted horizontally on a high surface like high branches of trees or ceilings in cases of home use.
Other larger types of PIR sensors are developed using single-segment mirrors and can detect infrared radiation energy over 32 meters from the sensor. Some PIR sensors are designed with reversible orientation mirrors that allow broad coverage about 110° wide, or narrow window coverage, or user-selectable segment to adjust the coverage.
In conclusion, the PIR mode on a trail camera is a feature that helps the camera work more effectively, the owner activates the feature on the camera and the sensor becomes active looking to detect motion based on sudden temperature change. Now the owner can relax not having to worry about the intrusion.
Understanding how your trail camera works is important to get the best out of it. Majority of people who use or own trail cameras go with a rather unconventional belief that their camera emits infrared beams and when that beam is interrupted or broken, it triggers the camera to take images. While this feature exists in some cameras, it is called the Active Infrared – AIR technology. Trail cameras instead, make use of passive infrared sensors – PIR. The PIR sensor is different from the active infrared because it receives information about movement and temperature. When the PIR sensor detects a difference between the object moving and its immediate environment, it signals the camera which in turn takes a picture of its line of sight.
When a warm body, for example, an animal or a human walks inside or into the line of sight of the camera, the infrared adjustment inside the range triggers the PIR sensor to take images. Trail cameras have this feature regarding their motion recognition frameworks, based on the fact that PIR frameworks are separated into two sections namely; Infrared estimation, and genuine motion of the object.
As a trail camera owner, you must understand the idea that every living thing emits infrared by radiation. Evolved animals, birds, grasses, and trees all emit various typical dimensions of infrared radiation. The hotter it is, the more radiation give off or emanation.
Altering the affectability on the PIR sensor will give you a little control over the dimensions of the IR radiation an object should emit before triggering the sensor. Reducing the affectability setting will help with false triggers commonly caused by leaves falling and the wind blowing through the grass.
In conclusion, the PIR sensor is triggered by movement or motion by objects. These objects in motion could be an animal, say a bird, reptile, or vegetation too. Hence, understanding your camera and knowing what triggers the camera to take a picture can help you in planning to prevent the chances of false triggers.
To activate the PIR mode of a trail camera, follow the steps below;
- Turn ON the camera by pressing and releasing the power button.
- Ensure the installed battery contains the adequate charge level before you proceed.
- Go to the ‘menu’ option and select ‘Trigger’, the highlighted option will be blinking.
- Use the left or right navigation button to move to different options, press the OK button to save the setting after selecting ‘PIR mode’.
- Click the OK button while PIR mode is selected, the highlighted option will be blinking.
- Use the left or right navigation buttons to select from the options; ‘still’ or ‘video’.
STILL: The camera captures still images.
VIDEO: The camera records 30 seconds of videos.
- Go back to the menu, select ‘PIR active’, and then select between ’24 hours, day or night’.
24 hours: The PIR mode stays active all day long.
DAY: The PIR mode stays active only during daylight.
NIGHT: The PIR mode stays active during the night.
There is a widespread conflict on the functionality of PIR sensors during daylight. While a greater majority of people believe that PIR sensors work during daylight, some, however, do not.
The PIR sensor of cameras can work all day long. They’re not exactly affected by daylight or ambient light. When the condition of the environment surrounding the camera changes slowly, the PIR sensor adjusts slowly to the changes. It is the sudden change in the radiant heat of the environment on the camera’s line of sight that triggers the sensor. However, it is possible for the sun to rapidly heat the surface around the PIR FOV of the camera and cause a false trigger. Although this false-triggering situation rarely occurs.
PIR sensors can work during the day because they detect ‘sudden change’ in their immediate environment. The temperature change accustomed during daylight is not sudden; hence, the sensor is oblivious to such changes.
Testing PIR functionality during daylight is normal to determine the effect of the sun or ambient light on the sensors. When a PIR detects movement, the outward pin goes as high as 3.3V and then, lights up the LED. When you have wired up the breadboard, insert the batteries and wait for about 30-60 seconds for the PIR to come up and fully stabilize. During this time, the LED may blink a little, wait till the LED turns off and then move around and in front of it, waving a hand, gesturing, or performing any motion-related activity to see if the LED lights up. If it does, it clearly shows that it is not affected by the sunlight or ambient light.
The functionality of a trail camera during daylight could also be tested by perfectly standing still in front of the sensor and waiting till it adjusts, then checks what the least motion is to cause it to trigger by moving a little away from it.
Exposing the camera to a substantial amount of sunlight while someone moves across the camera’s line of sight could also be used to test its functionality during the day. However, the product specifications and user manual warn against exposure to direct sunlight. This precaution is very important because the sun is, as we all know a massive source of infrared radiation that can make discerning small changes or motion in infrared radiation from a person or object moving difficult.
Over the course of this article, we have stated that PIR sensors detect a change in the temperature by noticing the heat emitted by an object or reflected from it through radiation and in turn, triggers the PIR sensor to take pictures in its line of sight.
Animals are the closest creatures to man and most times, security cameras around our property get triggered only for you to find out it was triggered by an animal. The PIR mode feature present in trail cameras is a very important and functional part of these cameras that have made them exceptionally popular for use in either hunting or watching animals. Animals have a standard body temperature of about 36°c to 39°c. So when an animal passes the line of sight of a trail camera which has adjusted to the temperature of its surrounding, it detects the animal immediately because the animal gives off different IR radiation which triggers the sensor to take images.
In most cases, the efficiency of these sensors to detect these animals is dependent on the camera angle or range. Cameras with angles greater than 180° cover much field of sight than those with lesser value.
PIR sensors detect infrared light emitted from objects that produce ‘heat’, and inevitably, infrared radiation in its line of view. The crystalline material at the center of the rectangle on the face of the sensor detects the infrared radiation. The sensor normally splits into two halves to detect the change in the temperature that happens when a target object enters its sight and not the radiation itself.
From the above explanation, we can agree that a car falls into the description of objects that can be affected by PIR sensors. Cars emit a high amount of heat when active, hence when moving across the sight of the camera at a steady pace it can trigger the camera to detect its motion. However, when the car is moving at a fast speed, the trigger speed of the camera will usually determine if it will trigger the shutter and if an image with the car is captured or not.
Newer models of PIR sensors are now more sophisticated and reliable. They have a lower false alarm frequency compared to their predecessors. They can distinguish animals and humans and can also be used for detecting hot object movement due to limitations caused by the usage of a simple comparative structure inside that cannot be altered; that is not flexible for development or suitable for algorithms. Based on the functionality of PIR sensors and their ability to detect heat, they can be used to detect a fire, especially when the fire sparks out suddenly.
However, PIR sensor cameras are not widely used for detecting fires in homes; rather, the flame detection system is used for fire detection in large rooms. An uncontrolled fire flame flicker process and the ordinary activities of humans are used in modeling a set of hidden Markov models (HMM) which are trained using the wavelet transform of the PIR sensor detector. When there is an activity that falls within the viewing range of the PIR sensor system, the signal given off by the sensor is analyzed in the wavelength domain, the signals are sent to a set of HMMs that in turn, makes a decision of a ‘fire’ or a ‘no fire’ situation based on the particular HMM producing the highest probability.
The flame detector is a sensor that is designed to detect and respond to the presence of a fire, by allowing flame detection. The response to fire detection is dependent on the installation system but could include sounding an alarm and activating a fire suppression system.
The answer is No. PIR sensors do not work through glass. A PIR sensor is a form of a motion sensor, and motion sensors cannot work through the glass because they make use of the PIR technology to detect movement. A change in infrared radiation cannot be easily detected through a piece of glass or a glass panel. This is why PIR sensors cannot work through windows because they are mostly insulated and these glasses, especially the new ones, are uniquely designed to stop most, if not all, Infrared radiation.
There are however some exceptions to this rule. Non-insulated glass and older plate glass may allow a high amount of infrared radiation to pass through them and maybe enough to trigger the PIR sensor. Also, light passing through a window may result in enough of a change to deceive a PIR sensor into triggering. This is why PIR sensors are usually recommended to be placed away from windows to prevent false alarms.
Some of the common issues you might face when using a PIR security camera behind or through a glass window at night is ‘window glare’ either by ambient light or IR LEDs. A window glare or glass reflection is most likely to make an image white-out or make a video look washed due to the overexposure of lights at night that makes it hard to sort out the details. On the other hand, during the day to me, the cameras work very fine.