Choosing the best thermal monocular can be a challenging task due to the wide variety of models and brands available on the market. The arrival of thermal clip-on devices for scopes has made this choice even more complex. Below, we offer a detailed guide to help you understand the key factors and make an informed decision.
What is a thermal monocular?
A thermal monocular is a device that uses thermal imaging technology to detect and visualize temperature differences. This is especially useful for hunting, surveillance, and outdoor activities in low-light conditions or complete darkness.
Technical factors to consider
Sensor size
Sensor size is crucial in determining image quality and the observation distance of a thermal monocular. Thermal sensors are generally classified into four sizes:
-
126x sensors
- Ideal for getting started in the thermal world.
- Allows short-range observations with basic image quality.
- Recommended for limited budgets.
-
256x sensors
- Offers better image quality and greater observation distance.
- Lenses with smaller diameters, limiting the observed distance.
-
384x sensors (and 400x)
- Considered the most versatile and popular.
- Allows the use of lenses with larger diameters, up to 50mm.
- Suitable for long-range observations.
-
640x sensors (and 1280x)
- Offer the best image quality and greatest observation distance.
- Ideal for advanced users and professional applications.
Microbolometer
The microbolometer is another essential component that enhances the thermal sensor. Currently, there are two main types:
- 17 microns: More common, but with fewer cells.
- 12 microns: Recommended whenever possible, as it offers a higher cell density in the same sensor size.
Display technology and resolution
Thermal monocular displays are generally 0,39” in size and can be of two types:
- LCOS (Liquid Crystal on Silicon): Offers more pixels, but not necessarily better quality.
- OLED (Organic Light Emitting Diode): Fewer pixels, but higher image quality and better battery management.
Thermal sensitivity (NETD)
NETD (Noise Equivalent Temperature Difference) is a parameter that measures the monocular's sensitivity to thermal variations. A low NETD value:
- Increases sensitivity to temperature changes.
- Reduces noise in the image, improving quality.
Lens size and field of view (FOV)
Lens size and the Core design determine optical magnification and FOV:
- 19-25mm lenses: Recommended for short-range observations.
- 35mm or 50mm lenses: Suitable for long distances, although with a narrower field of view.
Battery life
Battery life is a critical factor, especially for long observation sessions. The use of external batteries is recommended for greater autonomy, avoiding internal batteries, which usually last less time.
Usability
It is essential that the thermal monocular be easy to handle, especially in cold conditions with gloves or in situations with low visibility.
Technical issues and after-sales service
Like any technological device, thermal monoculars can have technical issues. It is crucial to choose a brand that offers good after-sales service and proper warranties.
Quality thermal monoculars at a good price
In today's market, thermal technology has advanced enough to find equipment with outstanding performance without the need to incur premium costs. A quality/price monocular is one that maximizes sensor resolution (pixels) and thermal sensitivity (NETD) relative to its cost. These are the 5 models that represent the best value right now, validated by our expert:
| No. | Brand and Model | Use Range (Quality/Price) | Expert Justification |
|---|---|---|---|
| 1 | ThermTec Cyclone 325 | Mid-range / Compact | It offers exceptional image quality for its price range (generally just over 1.000 €) thanks to its low NETD (sensor sensitivity). It is extremely compact and perfect as a first monocular or to carry with you at all times. **Maximum value for the lowest price.** |
| 2 | Guide TE421 | Mid-Low Range / Reliability | With a 400x300 sensor, a very compact size, and a very affordable price, this thermal monocular is one of the best options for those looking to get started in the world of thermal imaging. |
| 3 | ThermTec Cyclops 335 SE | Mid-Range / 384 Performance | An option that raises the bar. With a 35 mm lens and a 384x288-pixel sensor with very low NETD, this monocular offers great detection distance and detail for its price, competing with more expensive models. **Excellent balance between range, quality, and cost.** |
| 4 | Conotech Aquila 350LIIR | Mid-High Range / Integrated LRF | The laser rangefinder (LRF) is a key feature for any hunter or professional who needs to know the exact distance. This Conotech model offers an integrated LRF in a package with good performance and image quality. The number of optical magnifications is very important, as it allows us to distinguish what we are observing. |
| 5 | Nocpix Vista H35 | High-End / 1.03" Screen | A high-end model to keep in mind for the capabilities of its 1.03" AMOLED screen and 2560x2560 pixel display resolution. Among the best on the market in image quality and features. |
Conclusion
Choosing the best thermal monocular requires considering multiple technical and practical factors. Evaluating sensor size, display technology, thermal sensitivity, battery life, and usability will help you make an informed decision. For the best selection, always consult experts and check product recommendations at specialty stores such as Vision Nocturna y Térmica.
We hope this guide helps you find the perfect thermal monocular for your needs!