Thermal Sensitivity (NETD)

NETD (Noise Equivalent Temperature Difference) refers to the smallest temperature difference that a thermal imaging sensor can detect. In the context of thermal optics for hunting, a lower NETD value means that the thermal imaging sensor is more sensitive to changes in temperature, which can result in a clearer and more detailed image.

High-quality thermal imaging sensors used in hunting applications used to have NETD values ranging from 50-100 milliKelvins (mK). However, recent advancements in thermal imaging technology have led to the development of thermal imaging sensors with even lower NETD values. Hunting thermals can now come with NETD values as low as 18 mK.

For hunters, a lower NETD value can be especially beneficial when tracking game in low light conditions or when searching for animals that may be partially concealed by foliage or other objects. However, it's important to note that thermal scopes with lower NETD values may come with a higher cost.

When selecting a thermal scope for hunting, hunters should consider the NETD value of the sensor in addition to other factors such as pixel pitch and sensor size. A lower NETD value can contribute to a clearer and more detailed image, but may also come with a higher cost. Hunters should evaluate their specific needs and budget when choosing a thermal scope with an appropriate NETD value.