luminosity

It is the radiations of light which they throw off; it is their luminosity—their transparency.

There was luminosity where the ships had encountered each other.

Value or luminosity of colors ranges between these two extremes.

But this luminosity is not entirely confined to the minute creatures of the sea.

He nodded toward the circular area of luminosity on the sea.

Now the mist about him took on a luminosity which was of a different kind.

Abnormal darkness,” it was added, “follows as a reaction after luminosity.

If we need a noun we say "luminosity," which is abstract, being derived from an adjective.

We have been shooting like a meteor as to rapidity, but without its luminosity.

Mistcherlich's method is based upon the luminosity of the vapors of phosphorus.