Night Vision vs. Thermal Optics: What You Need to Know

The question is always asked, which is better, night vision or thermal? We will discuss the pros and cons of each, the true capabilities of each, and determine how best you will utilize these devices. As to the true answer to this question, the answer is both. These optics can be helpful in certain circumstances, so buying and using both options is recommended.

The price, capabilities, and limitations can vary depending on what you need the optics to do. Before you choose between thermal imaging and night vision, you must understand these technologies' differences. They are pretty significant, so you need to take the most responsible approach to consider this issue.

Thermal Imaging & Night Vision

Thermal imaging is the ability to detect heat (both day and night). This can be a game-changer in viewing, observation, tracking, hunting, and security applications. This technology's wide range of applications makes it in demand in various fields of activity. Such popularity is the engine of further progress, thanks to which thermal imaging is developing and becoming more perfect. However, thermal does have its limitations. Thermal imaging utilizes a digital image of what you are looking at (much like a camera). The quality of this image is measured in pixels. The higher the number of pixels, the more precise the image. However, when zooming in or increasing the magnification of thermal devices, you reduce the pixel count in half with each doubling of magnification. This leads to the appearance of various defects that reduce the clarity and detail of the image. Same as your cell phone, the image quality deteriorates as you zoom a greater distance.

On the other hand, night vision is an optical system, as you pull light in and amplify your current situation by utilizing an image intensifier tube. This design element is critical to all NVDs. It is he who provides various manipulations with light, as a result of which the image becomes brighter and more transparent. At the same time, the image intensifier can work effectively only after dark. This means that night vision does not serve a purpose in daytime use. It also means that Night Vision provides an accurate optical view of the image you are looking at, the same as a daytime scope. Night Vision does require some light (moonlight, ambient light, infrared light) to provide a clear and bright image. Without it, any NVDs will become practically useless optics.

In many cases, the stars and moon will provide enough light to produce an image, but shadows can make it hard to see. This often occurs in cloudy weather, when clouds cover the light of celestial bodies. Similar situations are also possible in fog, sandstorms, or heavy smoke. To solve this problem, an additional structural element is required to compensate for the lack of natural light. Due to this, most night vision comes equipped with an IR Illuminator, to be utilized when you do not have ambient light or need a beam of infrared light to illuminate an object.

To truly determine a better application for your environment, let’s look at the below breakdown of features and specifications.

Design

One of the main differences between night vision and thermal imaging lies in the very design of devices that support this technology. Because of it, the difference becomes noticeable in the size and weight of the optics and the configuration. Each type of device has its design details that are used exclusively there. This makes them unique and not similar to vehicles from another category.

Models with night vision have a unique image intensifier tube (IIT) in their design. It converts the light the device collects into an image the human eye can see. There are several generations of IIT. The simplest of them (Gen I) are practically not used nowadays and are found only on obsolete NVDs. More modern IIT eras, Gen II and Gen III, are most in demand in our time, and almost all NV devices are created on their basis. There are also several intermediate generations of IIT (e.g., Gen II+, Gen III+). Each type of this structural element has its characteristics and includes its parts. This gives a particular variety and allows you to create many different models of night optics.

Devices that support thermal imaging do not have IIT in their design. The collected IR rays are converted into a thermal image using a unique electronic system. It transforms the electrical impulses created based on the infrared radiation received by the device and displays the finished result on the optics display. In addition, the design of thermal imaging models contains lenses of a larger diameter than NV optics. It is this feature that forces manufacturers of thermal imagers to increase the dimensions of their products. A larger lens diameter is needed to increase the efficiency of collecting IR rays. If you use optical elements similar to night vision models, more than the resulting source material will be required to form a high-quality image.

Operating principle

In principle, there is minimal similarity in operating devices that support thermal imaging and night vision. Each of them has several unique stages characteristic only of a particular technology. The only thing they have in common is simplicity. Thanks to it, even people without special education can understand all the nuances of the functioning of both types of devices.

Let's start considering the principle of operation with classical night vision devices. At the beginning of the process, the optics lens captures all available light in the area where the user directs it. The source material is collected after the light fluxes from various celestial bodies are reflected from all environmental objects. If there is insufficient light, then an IR illuminator comes into play. It generates light changes and replaces them with natural light. The resulting light is then focused and enters the IIT. Here, photons are instantly converted into a stream of electrons, with which all further manipulations are carried out. In a photomultiplier, the number of particles sharply increases, due to which their flux increases. At the next stage, the electrons enter the luminescent anode, where photons are knocked out under the influence of an electric charge. The latter forms a new multiplied stream that contains the original information. As a result of such actions, the original image becomes brighter, more transparent, and more contrasting. It is transferred to the display, where the owner can see it of NVDs.

With thermal imaging devices, the whole conversion process is different. At its first stage, the optics lens collects infrared radiation from any environmental objects (living and inanimate). It is focused and captured by the device's IR detectors. Due to their increased sensitivity, these design details do not lose sight of any beam, which allows you to get a complete image in the future. The so-called thermogram is formed from the obtained source material. It displays the temperature readings at every point in the terrain that the owner of the optics is examining. After that, various manipulations allow you to turn the thermogram into electrical impulses. They are sent to the electronic system of the thermal imager, where they are subjected to multiple influences. As a result, the device forms a thermal image and redirects it to the eyepiece of the optics, which are often combined with the display.

Detection

Thermal imaging detects minute differences in heat when detecting a game, a person, a pet, and heated parts of various mechanisms (for example, military equipment). This gives devices that support this technology the raw material for thermal imaging, which is displayed on the display optics. Thermal scopes detect radiation and do not require any visible light to produce an image. Thermal imaging devices can be used equally healthy day and night. In addition, they will become indispensable in conditions of complete lack of lighting. Animals generate heat and are warmer than their surroundings, making it possible to detect them at great distances using thermal imaging.

Night vision relies on at least some ambient light, making detection at great distances more difficult. If shooting at night, the moon and stars should provide sufficient light for a night vision scope. In the absence of natural light, IR illuminators generate light. They only sometimes give the desired result. Therefore they are an addition used only in the most challenging lighting conditions. Night Vision sometimes requires the object to be moving to detect it. In scanning a field, it is possible to skip over an animal bedded down with night vision, whereas thermal will identify through the brush or tall grass or is not required movement to recognize the heat source. This gives thermal imaging a particular advantage and increases its popularity among users.

Recognition and Identification

Once a live animal has been detected, a hunter needs to recognize and identify it before making any shots. Otherwise, there is a possibility of killing a representative of the fauna that environmental organizations protect. This circumstance will lead to many problems, resulting in a hefty fine or severe punishment. When using thermal, images are displayed as black and white or shades of color, and various colors represent temperature. Even though a live object can easily be detected using thermal, recognizing it and identifying it as the desired game at a great distance is more complicated. There is a significant jump in detection range and recognition range when using thermal devices, such as whether a dog or coyote is a calf or a pig bedded down. In addition, the identification of living beings is complicated because, with the help of a thermal imaging image, the user sees only the outlines of objects without any of their details.

Night vision, on the other hand, amplifies light. It does not have much variance between detection and recognition, as it is an optical visualization of the object you are looking at. Night vision is only problematic if the game is camouflaged or is standing still. For these reasons, Night Vision will always be superior in recognition and identification, whereas thermal is superior in detection. Depending on the range and distance you are hunting, you might receive all the credit needed from your thermal device. Therefore, it is best to utilize both technologies to their strengths.

Image creation

Creating a human-visible image is the main task of all night vision devices. This is done in various ways, but the result is approximately the same. The quality of the generated image directly depends on many factors, ranging from the characteristics of the optics to the conditions of its operation. Depending on the type of device, the resulting image may have several distinctive features.

For models that support NV technology, the generated picture is always one-color. In most cases, green is used as the main shade. Experts consider this color to be the least harmful to the eyes, so it can most often be seen on the display of optics. Recently, doctors have criticized this theory, and numerous experiments have only confirmed their guesses. With prolonged observation, the green color can lead to excessive eye fatigue. This will create some discomfort and may gradually worsen visual acuity. In this regard, in modern NVDs, you can often find other color variations. At the same time, the image remains monochrome, and changes in this aspect are not expected yet.

Thermal imaging devices form a multi-color image. Different shades on it indicate the degree of heating of a particular area. Warm colors (shades of red, yellow, and orange) are used to show the hottest points of objects, and cold colors (green, blue) are the least heated. This allows the user to see the approximate temperature of each observed object by which one can easily distinguish living objects from inanimate ones.

Environmental conditions

An essential aspect of the operation of thermal imaging and night vision is the ability of each technology to cope effectively with the tasks set only under certain environmental conditions. Depending on the user's needs, the optimal device can form a high-quality image in the presence of various interferences.

NV devices can work effectively only under favorable conditions. Any weather surprises are detrimental to them since even a simple cloud cover will lead to a lack of lighting, followed by a sharp deterioration in the image's quality. More severe weather anomalies (such as heavy rain or snow) will render NVDs useless for the user. Experts call the strength of night vision the ability to maintain efficiency in extreme cold. This feature makes most NVDs ideal for regions with very low temperatures.

Thermal imaging optics is fundamentally different from NV. It does not experience problems with the lack of lighting. Moreover, TI devices can handle various tasks well, even in total darkness. They can be used in all weather conditions, ranging from heavy rainfall to fog. Another essential advantage of thermal imaging is capturing the heat of most objects hidden behind various obstacles (for example, leaves and tree branches). This makes it effective in all environmental conditions, regardless of the amount of vegetation and other natural obstacles. Night vision does not have such an opportunity, which can only be helpful in open areas.

Price

For many buyers, the cost is essential to any night optics. On sale, you can find models from different price categories that will satisfy the needs of most users. The cheapest will always be devices that support night vision technology. At the same time, the cost of thermal imaging optics will almost always be higher. The exception may be older models, many of which are cheaper than modern NVDs.

Most often, the difference in price between devices of different types (with a similar set of characteristics and functions) is quite significant. It is made up of many factors that affect the cost. Chief among them is the complexity of the production of TI optics, which requires using modern equipment and purchasing components of the highest quality. In addition, some design features of thermal imagers increase the difference in cost. They use more expensive parts that take time and valuable materials to produce.

Classic NVDs are also costly devices. Often their cost exceeds several thousand dollars, which is commensurate with some models of TI optics. At the same time, most devices are affordable, and almost everyone can purchase them.

Application area

Night vision and thermal imaging are popular technologies. The devices created on their basis benefit representatives of various professions, opening up access for them to work after sunset. The primary users of both types of night optics are military personnel of multiple units. With their help, they perform a variety of combat missions, train at training grounds, shoot in the dark, navigate the terrain, and control military equipment in places without illuminated roads. NVDs and thermal imagers give soldiers an advantage over opponents, thereby increasing the likelihood of completing the tasks set by the command.

Night vision devices are famous for hunting and fishing. Thanks to their capabilities, it is possible to identify animals, move safely through unfamiliar terrain, shoot accurately, and monitor fishing tackle. NVDs are no less in demand in the industry. They are used during night shifts when the available lighting is insufficient to perform a specific job. Recently, night vision has been actively introduced into the automotive industry. It is integrated into the vehicle control system, thereby increasing the safety of drivers, passengers, and pedestrians. In addition, it is often used in civil aviation, science, and construction. Night vision also helps lovers to observe wildlife. In this direction, its capabilities are used to search for and keep animals that lead a nocturnal lifestyle. Even for entertainment purposes, different types of NVDs are in-demand devices. They complement participants' equipment in military tactical games and other similar competitions.

Thermal imaging is no less popular technology than night vision. It is actively exploited by military personnel and civilians. The latter finds many applications for various devices and gradually turns thermal imaging into an indispensable technology. Most often, ordinary people use such optics for hunting. It helps to reduce the time spent searching for animals and increases hunters' safety. Such devices are also popular in medicine. Thanks to their capabilities, diagnosing some dangerous diseases before the first visible symptoms appear is possible. For similar purposes, thermal imaging is also used in veterinary medicine. This optics brings many benefits to people representing different industries. It is indispensable for power engineers, metallurgists, and chemical and oil and gas employees. For entertainment purposes, thermal imagers are rarely used. At the same time, they are indispensable assistants to sports referees. With their help, representatives of Themis monitor compliance with the technical rules in cycling, auto racing, and motorcycle racing.

Thermal imaging optics and classic night vision devices have been indispensable human assistants for many years. Simultaneously, disputes continue about which technologies are more effective and valuable. There is no single answer to this question. Both options have their strengths and weaknesses, so they are the best choice only in some instances. At the same time, thermal imaging and classic night optics perfectly complement each other, so the best option is to own both types of devices simultaneously. They can compensate for each other's shortcomings and enable a person to see well at night.

You can find more information about thermal imaging and night vision here:
Night Vision vs. Thermal Optics: What You Need to Know
How Does Thermal Imaging Work?
How Does Night Vision Work?
In our store