This phenomenon, however, was almost certainly caused by Eigengrau or "dark light".

The title Eigengrau is the German word for the colour ("intrinsic grey") seen by the eye in perfect darkness.

Eigengrau is perceived as lighter than a black object in normal lighting conditions, because contrast is more important to the visual system than absolute brightness.

The noise probably originates from thermal noise exciting the photoreceptor cells in the retina; compare Eigengrau.

Penelope Skinner for Eigengrau (Bush)

Her play Eigengrau staged at the Bush Theatre in 2010 was a critical and box office hit and Skinner was nominated for the Evening Standard Award for Most Promising Playwright in 2010.

Eigengrau (German: "intrinsic gray" / literally: "own gray"), also called Eigenlicht ("intrinsic light"), dark light, or brain gray, is the uniform dark gray background that many people report seeing in the absence of light.

GG17 "Eigengrau" - remix album feat versions of various Section 25 remixed by the likes of Portion Control, Absolute Body Control, 23 Skidoo, Cabaret Voltaire's Stephen Mallinder, Renaldo and the Loaf and more.

Eigengrau (German: "intrinsic gray" / literally: "own gray"), also called Eigenlicht ("intrinsic light"), dark light, or brain gray, is the uniform dark gray background that many people report seeing in the absence of light.

They are said to differ from dreams proper in that hypnagogic imagery is usually static and lacking in narrative content, although others understand the state rather as a gradual transition from hypnagogia to fragmentary dreams, i.e., from simple Eigenlicht to whole imagined scenes.

Why did he now see himself in such dark light?

A dark light, hard to see and even more difficult to understand.

In dark light and at night, return to the 0 setting.

He looked up at me, his brown eyes filled with a dark light.

They are attracted to the dark light of it, understand?

It was hard to tell in the dark light, but she wasn't taking any chances.

There was a dark light in his eyes, something more primitive than we have words for.

The train is a line of dark light on the night plains.

He wondered what happened to his shadow, in this dark light.

And she knows it is full of dark light.

The concentration of power used to be seen in a dark light."

The dark light in her eyes was dim, barely focused.

For the evil man sees a dark light on the horizon.

He closed his hand instantly, frightened to look into its dark light.

He turned then, and his eyes were full of a dark light that had nothing to do with vampire powers.

While her dark light filled my eyes she saw what I saw.

His eyes had a sort of dark light to them, a sparkling blackness.

New ways were found to throw the Dark Light through the air.

In dark light, the keyboard backlight does its job fine.

Too much solitude feeds on itself and makes me see things in an overly dark light.

That box is filled with the Dark Light - but have no fear!

The forest beyond was cold and uninviting, gleaming with dark light.

Dark lights, like those left by flashbulbs, swam before his eyes.

Dark light was frightening enough even if you knew what was happening.

Are we talking about a device powered by the Dark Light?