Time and space are relative…Simultaneity is relative, as it depends on many factors… the way we perceive something or someone is deceptive. We experience this  reality by watching the light interacting with objects… we experience it through the light being emitted or reflected by surrounding objects, not by measuring it directly. And how the relativity affects that light? The speed of light doesn`t depend on the velocity of the source of light or the velocity of the observer, however the wavelength does.