Talk:Eigengrau

A fact from Eigengrau appeared on Wikipedia's Main Page in the Did you know column on 29 June 2006. The text of the entry was as follows:

Did you know... that even in perfect darkness, the retina spontaneously sends signals down the optic nerve, causing a sensation of gray called eigengrau?

A record of the entry may be seen at Wikipedia:Recent additions/2006/June.

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Questions[edit]

Okay, what else should I add to this? Got a question about eigengrau? Ask it here and I'll add the answer to the article. —Keenan Pepper 02:00, 27 June 2006 (UTC)[reply]

I obviously know nothing about this field, but I'll take a shot: what does it mean to say that the sensation is a uniform dark gray? Couldn't the sensation be called "black" in the sense that there one cannot perceive a darker shade? Or would we reserve the word "black" for zero-temperature eigengrau? Or, perhaps, is there an even darker black caused by, say, temporary nerve damage? Melchoir 17:31, 27 June 2006 (UTC)[reply]

Good question. You can indeed perceive darker colors than eigengrau. In fact, ordinary black objects are darker than eigengrau, because it's all about contrast. —Keenan Pepper 21:55, 27 June 2006 (UTC)[reply]

Very interesting... now, when we say that a black object in a non-black environment is darker than eigengrau, is that a comparison of nerve firing rates, or some kind of perception experiment, or perhaps both? Melchoir 07:09, 29 June 2006 (UTC)[reply]

I think it's just a psychological effect, not physiological, but I'm not sure. I'll look it up. —Keenan Pepper 15:42, 29 June 2006 (UTC)[reply]

Okay, I found some research that shows that stimulation of one region of the retina inhibits neighboring regions, but the journals (J. Opt. Soc. Am. 53 and 54) are in my library's "remote storage" so I won't have access to them for a few days. —Keenan Pepper 23:07, 29 June 2006 (UTC)[reply]

Excellent. Thanks! Melchoir 01:46, 30 June 2006 (UTC)[reply]

It's great - love the word - can you tell us who coined it?, who first observed the phenomenon? Adambrowne666 06:57, 29 June 2006 (UTC)[reply]

My guess would be Hermann von Helmholtz, just because he's so smart and did all kinds of pioneering work in this field. I'll look it up later today and see if I'm right. —Keenan Pepper 15:42, 29 June 2006 (UTC)[reply]

The earliest reference I've been able to find is Hermann Aubert's Physiologie der Nezhaut, 1865, but I can't find it at my library. Is there anyone who has access to this book or can verify that Aubert first observed and named eigengrau? —Keenan Pepper 23:07, 29 June 2006 (UTC)[reply]

Fascinating... my only suggestion for improvement would be to rephrase some of the Causes section to make it more accessible for a layperson (someone like myself who might know only basic concepts of the physics of light) to understand. Also, has any of the experimental data come from human patients with damaged retinas? Analogous to the discovery of "language centers" in the brain located in people with speech disorders? -Fsotrain09 16:34, 29 June 2006 (UTC)[reply]

maybe it would be original research, or maybe somebody HAS done the research, but there appears to be a connection between eigengrau and the phenomenon known as "the greys." these are "humanoid" grey entities seen by individuals in their darkened bedrooms while these people are on the cusp between wakefulness and sleep (or sleep and wakefulness). some individuals actually claim that they are seeing "aliens,' but eigengrau (or hypnagogic or hypnopompic hallucinations) would be a more reasonable hypothesis........— Preceding unsigned comment added by 50.195.22.209 (talk • contribs) 07:10 17 November 2012

Sources for colour infobox[edit]

Where are the sources for the colour infobox? I doubt there is knowledge on what is the exact hue of visual system random noise. I'm going to comment it out until someone can source it. --Cyclopia ^talk 07:59, 24 June 2013 (UTC)[reply]

It seems this was added (the HEX value at least) in these revisions:

[1]
[2]

The oldest "source" I could find online is this: [3]

It would seem the HEX value was defined by some user named "Chi" on March 13, 2009. Seems a bit arbitrary to say the least. I did a web search for sources before that date and could find none. No scientific or mainstream source points to the HEX value as so. Considering how long it has been on the Wikipedia page, it may pop up later on a source simply due to the fact it was on Wikipedia. Kind of makes you wonder what other "facts" get made up here. SchizoidNightmares (talk) 08:28, 3 November 2020 (UTC)[reply]

According to George Trumbull Ladd, Direct control of the retinal field, 1894: "The color of the 'Eigcnlidht' had (i.e., ordinarily on beginning the experiment) the appearance of a dancing mass of vari-colored dust, red predominating.", and it's probably not even relevant to the full field of view. However in case it should be a reddish gray, not a bluish gray. --ElfQrin (talk) 12:35, 18 July 2023 (UTC)[reply]

Assessment comment[edit]

The comment(s) below were originally left at Talk:Eigengrau/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Was on MP Did you know?

Last edited at 19:53, 26 August 2006 (UTC). Substituted at 14:15, 29 April 2016 (UTC)

Color infobox again[edit]

The color infobox has been returned after being commented out previously. As noted above, it seems pretty dubious to give a specific color with its RGB values for eigengrau, unless if sources indicated that someone had actually devised an experiment to measure it. There is probably personal variation in what people see when there is no light anyway, and it may not even make sense to represent eigengrau as a color on a computer screen, or classify it as a color at all. Nat2 (talk) 15:53, 20 August 2016 (UTC)[reply]

The 'colour' shown is complete and utter nonsense. Even if it were possible to arrive at an RGB value for perceived colours (it isn't), there is no way to accurately show the difference between 'Eigengrau' (which can only be seen in the absence of a light source), and the 'black' value shown, which isn't actually 'black' at all on any conventional display technology. Displays emit some light even for 'pure black' RGB values, and even if they didn't the screen reflects some ambient light. 86.173.138.228 (talk) 20:14, 19 April 2018 (UTC)[reply]

Title and usage[edit]

As the article notes, the usage of eigengrau and eigenlicht have been declining over time: see, for example, [4]. This graph casts doubt on the claim that 'Eigengrau' has been in use since the 19th century, although 'Eigenlicht' apparently has; in general and currently, Eigenlicht is a more common term. Maybe the title should be changed. Nat2 (talk) 16:17, 20 August 2016 (UTC)[reply]

Hex Value[edit]

Okay. I know that there is little known about the origin of #16161d, but at this point, it seems like that's the accepted value of Eigengrau. At this point, I think it's worth mentioning this value. Something along the lines of. "Eigengrau is often represented as the value #16161d, but this value's origin is unknown." I don't think we should ignore this. --Diriector_Doc├─────┤^Talk_Contribs 20:51, 23 March 2022 (UTC)[reply]

A hex value that has no proper sourcing isn't of much worth, especially when it's arguably outright wrong (as above). A lot of the sites repeating the dubious information are scrapers, and a fair number of them took the information from Wikipedia while it was still present (even using the same graphic to display it). The Internet's full of oft-repeated things, but that doesn't make them correct or worthy of inclusion. Unless a proper reliable source publishes on it, I still see no reason to mention it. --Xanzzibar (talk) 21:26, 23 March 2022 (UTC)[reply]