We tested the Illuminator system in four categories: Absolute Brightness
, Even Illumination, Relative Brightness, and Contrast Ratio.
The SDSS project entails systematically mapping one-quarter of the entire sky, producing a detailed image of it and determining the positions and absolute brightness
of more than 100 million celestial objects, according to the scientists.
New from Tricor Systems are 820 Series video photometers that measure the absolute brightness
of any size sample in f[lambda] or cd/[m.
If we make a scatter plot of color versus absolute brightness
(luminosity), most stars fall roughly on a line, called the main sequence.