Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
photographic magnitude:see magnitudemagnitude,
in astronomy, measure of the brightness of a star or other celestial object. The stars cataloged by Ptolemy (2d cent. A.D.), all visible with the unaided eye, were ranked on a brightness scale such that the brightest stars were of 1st magnitude and the dimmest stars
..... Click the link for more information. .
photographic magnitudeSee magnitude.
photographic magnitude[¦fōd·ə¦graf·ik ′mag·nə‚tüd]
The magnitude of a star, as obtained by measuring the apparent size of a star's image on a photographic emulsion sensitive to blue light at wavelengths between 400 and 500 nanometers.