The magnitude of a star in yellow-green light, the centre of the range of wavelengths to which the eye is sensitive, on the system of Johnson photometry. The V filter has a central wavelength of 545 nm and a bandwidth of 84 nm. It is the photoelectric equivalent of the older photovisual and visual magnitudes. There are also V filters in Geneva photometry, Vilnius photometry, Walraven photometry, and the six-colour system, but the context should always make it clear when these are intended.
Subjects: Astronomy and Astrophysics.