Night Vision vs. Thermal
Thermal because than its surroundings, Optics the subject’s detect the temperature radiation thermal or optic heat, is higher will and provide an image. Since they detect radiation, thermal optics do not require visible light. Night vision requires a light source to provide an image. In many cases, the stars and moon provide enough light to produce an image, but shadows make it difficult to see small details. Heat radiation and light are both parts of the electromagnetic spectrum, but an optic designed to amplify light won’t see radiation energy, and vice versa.