Wavelength variation comes in three ways. They are subjected to the purpose of how and where you apply them.730nm is used when the only highest range is required. It gives off a semi-visible red glow, and most cameras are sensitive to it.850nm is generally used in almost all applications since it covers greater detail in further distances. It gives off a nearly invisible glow, and only some cameras pose sensitivity to it.940nm is utilized in applications that require covert operations. It does not produce any visible glow. However, 940nm IR renders less detail and reduced distances.