Night Vision Vs. Thermal

Seeing the nighttime world through a good pair of Gen 3 night vision can be a life changing experience. My first night with night vision equipment was a Gen 3 PVS 7. Those are the cyclops looking goggles with one Night vision tube split between two eyes. It was a magical experience being able to turn night into day; millions of stars dotting the sky, incredible resolution, I could make out fine details off in the distance like a bird leaving a branch 100 yards away.

My first experience with thermal was quite the same way; simply magical. My first hike with thermal was to detect animals to photograph for a separate wildlife photography blog. At one point there was a tall clump of reeds with a deer hiding directly in the middle. On thermal he was as clear as day. Without thermal I couldn’t see him in the tall grass at all.

So which is better in survival situations? Night vision or thermal? This is often debated and the best answer is probably both! They each really serve different purposes. That being said, they are also both very expensive investments and you may decide on purchasing either one or the other. Having had experience with both I’ll go over some of advantages and disadvantages of each, starting with generalities and getting more specific as the article goes on.

Night Vision:

Uses:

Night vision gear is outstanding for navigation. Whether goggles or a monocular, typical night vision has a magnification factor of 1x. This gives you a great view of your surroundings at close range and allows you to navigate, look at your feet for obstacles, and scan while having a “normal” view. Check out my site on PVS-14 night vision to see how the newer PVS-14 has a few advantages over the older PVS-7.

Below is a list of what I see as the most important advantages and disadvantages when considering night vision vs. thermal for survival situations:

Advantages Over ThermalDisadvantages
No Image lagNeeds some form of natural or IR illumination
Longer battery lifeThreat detection can be difficult.
Higher resolutionShadowed areas can remain dark.
Threat identification
More rugged (Military grade)
Waterproof
Mountable behind a scope (Monocular)

Threat Identification and Resolution:

In the above table I list threat identification as an advantage and lack of threat detection as a disadvantage. This is probably the main difference where utility is concerned and if you did acquire both you would use thermal for threat detection, and night vision for threat identification. Here’s an example, You’re out camping one night and you clearly see someone walking towards you through thermal because they’re lit up light a Christmas tree against the cool surroundings, but you can’t tell if that person is your cousin who’s camping with you for the weekend, or the guy who just escaped from the institution and is looking for their next “friend”. You raise up the night vision and can clearly see it’s your cousin. The reason for this is the much higher resolution of night vision equipment, and the tonal variations it is able to pick up. It’s like looking at the world in black and white, or green and white, depending on the phosphor.

Longer Battery Life:

With night vision you can typically expect 40 hours of use from one AA battery. Some devices last even longer. With thermal, depending on the unit, you might get 2-5 hours before you need to change the batteries or recharge the device. This is due to the fact that with thermal you are viewing a tiny LCD or OLED screen that needs to be powered, as well as all of the computation that occurs on the chip before the image is sent to the screen. Night vision on the other hand is turning photons into electrons and amplifying those electrons before sending them through a phosphor screen where they’re converted back into photons for your eyes to see. This process is extremely efficient when compared to thermal devices.

More Rugged:

A good PVS-7 or PVS-14 will be both waterproof to around 60 feet and rated to be mounted to a weapon without being destroyed by the recoil. Thermal monoculars are not typically designed to take such extreme conditions, and the weapon mountable versions typically don’t make great monoculars. Another benefit of Night vision devices mounted to a weapon is that they can be placed behind a scope since they amplify the visible spectrum. IR light won’t pass through glass so thermal units need to have a built-in reticle and cannot be used behind a scope. That brings me to another point, in a bugout SHTF scenerio, you wouldn’t be able to drive with a thermal device because it won’t see through the windshield.

Thermal:

Uses:

Thermal monoculars are great for threat detection. A good thermal unit can detect a human out at 800 to 1000 yards. Since they operate based on heat they are great for detecting all kinds of wildlife whether it’s moving or not. I’ve actually been able to navigate at night with a 1x thermal monocular but 1x versions are becoming more rare in my opinion. This is partially due to companies realizing the majority of their customers are hog hunting and want further detection ranges. Therefore, instead of increasing the resolution of the device, it is much more economical to increase the magnification of the lens itself. This has led to more and more thermal monoculars coming with 1.8x, 2x, or 2.5x magnifications. Great for distinguishing a hog from a human at 800 yards but not so great for trying to not trip over logs at 2am.

This has been a very general overview but I hope it’s given you some useful information if you’re trying to decide between night vision and thermal technologies.

Optics Planet is my go-to for night vision and thermal gear. Check out some of the options below:

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