How to choose thermal imaging and night vision

Customers often ask us what night vision and thermal imaging equipment to choose from our selection of products. However, the answer is not quite so simple. It depends on a number of factors. Firstly, you should establish for what purpose you want to use the device and what you expect from it. For starters, let's get familiar with the features and functions of each group.

THERMAL IMAGING

It is currently the most advanced technology for observing your surroundings in total darkness regardless of fog, smoke or dust. This is especially useful for hunters who spend most of their time outdoors and are at the mercy of the quirks of the weather. 

The hunt itself is much more effective, because the animals cannot hide from the thermal imager even in thicker vegetation or tall grass. It is also easier to track injured game. With thermal imaging, you can follow the trail of still-warm blood all the way back to its unfortunate owner.

Thermal imaging is of course also widely used by the military. After all, it is originally a military technology. The advantages it provides are invaluable on the modern battlefield. Just look at a few recent military engagements. However, in addition to soldiers and hunters, this technology is also used by various security agencies to safeguard facilities and protect people and property. But it can also be used to locate heat loss or in the medical field.

HOW IT ALL WORKS?

The thermal imager records thermal (infrared) radiation, which it then converts into a thermal image, called a thermogram. Unlike night vision, it does not rely on residual ambient light or external illumination. You can therefore use these devices day or night.

At the heart of every thermal imaging system is a special sensor called a microbolometer. It registers infrared radiation and converts it into electrical signals, which are then processed and transmitted to the device's display.

Thermovision measures the temperature distribution of an object and converts this data into an image. Objects will therefore be visualized in different shades depending on their temperature. The resulting contrast between the differing temperatures makes it easier to identify individual targets. Modern thermal imaging devices usually have multiple colour palettes for greater flexibility.

IMPORTANT PARAMETERS

Refresh rate

For smooth and undisturbed vision, the thermal imaging should have a refresh rate of at least 25 Hz. This number indicates how many times per second the output image is refreshed. The more the better. 

Resolution and sensitivity of the thermal imaging core (NETD)

The quality of the image itself is affected by the resolution of the microbolometer (thermal imaging core). Higher resolutions ensure better rendering of the observed object. The thermal sensitivity of the core (NETD) cannot be neglected either. This value is measured in millikelvin (mK) and determines the minimum temperature difference that the thermal imaging system is able to detect. Higher sensitivity = more accurate temperature detection (lower value means higher sensitivity).

Lens size

Another equally important parameter is the lens diameter, which directly affects the detection distance. Some advanced models, such as the Hikmicro Falcon FQ35, can detect a human being at distances exceeding 1500 m.

Battery life

This parameter determines how long the thermal imager will last in full operation before the battery needs to be recharged or replaced. 

Recording options

A variety of thermal imaging devices are capable of capturing visuals either in the form of video or still images.

Connectivity and compatibility options

Some models offer connectivity to other electronic devices such as smartphones, tablets or computers. You'll also often come across Wi-Fi functionality.

TYPES OF THERMAL IMAGING

We offer several types of thermal imaging equipment. Each has its own advantages and intended purpose. In the following paragraphs we will try to categorize the different types as clearly as possible.

The Hikmicro LYNX PRO LH19 thermal imaging monocular in action.

THERMAL RIFLE SCOPES

Thermal scopes replace conventional rifle scopes. They are mounted directly on the weapon and have their own reticle. Due to the large number of sophisticated components, it is important that the thermal scope on the rifle is as durable as possible and can withstand recoil from powerful hunting calibers. This unfortunately reflects adversely on their price. On the other hand, you get a high-end optical sight that combines the features of a classic rifle scope and modern thermal imaging technology.

MORE THERMAL IMAGING SCOPES

OBSERVATIONAL THERMAL IMAGING

Thermal monoculars are a great choice for unobstructed observation of your surroundings. They are usually compact devices that you can easily stash in your pocket and start enjoying the beauty of nocturnal nature whenever you please. They are mainly used by hunters, but are also popular with outdoor enthusiasts or security services.

MORE OBSERVATIONAL THERMAL IMAGERS

THERMAL BINOCULARS

These optical devices combine thermovision technology with conventional binoculars. They fulfil a similar function to thermal monoculars and are therefore mainly used to observe your surroundings. However they are somewhat larger than monoculars and you can't just put them in your pocket. Nevertheless, this is a small price to pay for the full range of advanced features they offer. 

For example, the high-end Hikmicro Raptor thermal binoculars provide users with a unique combination of thermal imaging, IR night vision and a laser rangefinder.

MORE THERMAL BINOCULARS

 Thermal Clip-On Sights

Thermal clip-on sights are a compromise between a thermal rifle scope and a monocular. You can use them as a classic spotting scope, but if needed they can also be clipped onto the lens of a rifle scope and you instantly have a device that uses the magnification of your rifle scope and functions as a thermal sight.

This modularity is especially invaluable for hunters, as they no longer have to cumbersomely maneuver the entire weapon every time they want to survey the terrain. When the moment is right, simply put the clip-on sight on the lens and you're ready to take aim. You don't have to reset anything, and your eye relief and cheek weld positions are preserved.

Don't forget to check out our selection of thermal imaging accessories.

MORE THERMAL CLIP-ON SIGHTS

NIGHT VISION

Devices using night vision have recently become very popular, mainly due to their availability and a lower purchase price compared to thermal imaging. They may not offer as extensive capabilities as thermal devices, but a wide range of users still find them invaluable. 

The ability to see in the dark is an extremely valuable asset in a wide range of applications. Aside from the armed forces, it is particularly useful for hunters. Observing the nocturnal movement of wildlife or even night hunting is now common practice. And all thanks to night vision devices. This technology is also widely used by security agencies to protect land or property.

HOW DOES IT ALL WORK?

Night vision is amplified by residual light, which can come from the reflection of the moon, stars, street lights or external illumination. These devices are divided into two basic types depending on their design - digital and analogue.

ANALOGUE NIGHT VISION

These devices work based on the principle of noctovision and directly amplify the residual light from the night sky or from an additional IR illuminator. It is an older technology, using photocathode tubes to convert light into an electrical signal, which is then amplified and converted into an image using electronic components. The image is usually displayed as monochromatic greyscale.

Analog night vision is characterized by its higher sensitivity to light and its ability to show details even in low light conditions. On the other hand, you'll face more static and less accurate colors.

MORE DIGITAL NIGHT VISION DEVICES

IMPORTANT PARAMETERS

Generations of night vision

This parameter indicates the residual light amplification capability and overall performance of analogue night vision.

• Generation 1 (GEN 1) was used during the Vietnam War and can intensify residual light by about 1000 times. At night, it requires at least moonlight or another infrared light source.
• Generation 2 (GEN 2) is probably the most popular form of night vision today. It uses a micro-channel plate that acts as an electron multiplier. This allows it to amplify ambient light up to 20,000 times. It is therefore already usable even on moonless nights.
• Generation 3 (GEN 3) uses similar components as the second generation. However, the biggest difference lies in the gallium-arsenide photocathode layer, which allows residual light to be multiplied by up to 50,000 times.
• Generation 4 (GEN 4) is the newest and most advanced form of night vision. It is characterized by a significant improvement in image sharpness and noise reduction even in low light conditions. Devices using Gen 4 also respond better and faster to exposure to bright light sources.

Type of illumination

If you find yourself in a situation where you can't get enough moonlight or other residual light sources, infrared or laser illumination will be your only hope. The latter is most commonly available in two wavelengths - 850 or 940 nm. The first option is at the very edge of the spectrum visible to the human eye. The second option is not visible to the human eye at all. Wildlife also does not respond to this illumination.

Battery life

A parameter that determines the time after which the batteries will need to be recharged or replaced.

Recording options

Most digital devices can capture photos or even videos.

Connectivity and compatibility options

Connectivity to smartphones, tablets or computers is standard on most digital devices, as is Wi-Fi functionality.

TYPES OF NIGHT VISION

NIGHT VISION RIFLE SCOPES

This is the most convenient way to mount night vision on your weapon. These sights will replace a traditional rifle scope because they have their own crosshairs and can function in daylight mode. Unlike frontal and rear clip-on sights, you don't have to worry about changing the rifle's center of gravity and the sighting itself is also noticeably more practical. However, monoculars or binoculars are better suited for longer-term observing.

Night vision riflescopes are jam-packed with features. In addition to the now standard Wi-Fi or Bluetooth, there is also the possibility of recording videos triggered by a shot, several types of reticles and, last but not least, the possibility of multiple guns being used and then stored into memory.

MORE NIGHT VISION RIFLE SCOPES

FRONTAL CLIP-ON SIGHTS

Frontal clip-on sights magnify your daytime optics and allow you to acquire targets at night. Just attach the sight to the lens in the front of the riflescope, hence the name. A huge advantage is the ability to use the frontal clip-on sight as an observational monocular and simply clip it onto your scope if needed. You don't have to reset anything, just make sure you have the appropriate scope adapter.

REAR CLIP-ON SIGHTS

The same applies here as in the case of the frontal clip-on sights, the only difference being that the device is mounted on the rear of the rifle scope. The rear clip-on sight can be used as an observation monocular and when mounted on the eyecup of your daytime riflescope, it instantly becomes a night vision scope. The rear clip-on sight uses the magnification and crosshairs of your optic without the need to refocus.

MORE REAR CLIP-ON SIGHTS

MONOCULARS

Monoculars are lightweight and compact devices for nighttime nature observing. They can be easily operated with one hand and you only use one eye when looking, which unfortunately reduces their field of view. However, this shortcoming is compensated by their compact size and light weight. You can carry them in your pocket without any trouble.

MORE MONOCULARS

NIGHT VISION BINOCULARS

Night vision binoculars allow full nocturnal observation of wildlife and objects. It is an excellent tool for hunters. Compared to a monocular, it offers a much larger field of view, which is however compensated by its larger size, weight and higher purchase price.

Don't forget to also check out our selection of night vision accessories.

ALL NIGHT VISION ACCESSORIES

IN CONCLUSION

Ultimately, thermal imaging and night vision serve the same purpose, and that is to enable users to see in the dark or in low light conditions. However, the two options differ in how they achieve that purpose. Night vision amplifies residual light, while thermal vision enhances infrared radiation.

Now it's up to you to weigh up the pros and cons of both technologies and decide which of the available options is the best choice for your needs.

We hope that this article has made your decision a little easier. If you're still unsure, please don't hesitate to contact us.