What's the wavelenght of pure red

[BurningLaserGuy]

@DJNY: I didn't see any reason for the neg rep that you gave to me. I mean there are a lot of the same type of threads, and they aren't useless or something. I also saw a pool called "What's the pure wavelenght of brown" - This IS useless, but is cataloged with five stars...this is annoying.

 

[IsaacT]

HERE is a proper outlet for all this. Be civil when posting there please.

 

[BurningLaserGuy]

I don't think I'll post there... You maybe saw my signature, and if yes you saw this: "What about we cannot speak about we must pass over in silence". Well, this is equivalent with: What about you aren't a expert don't post to. I am not an expert or at least an skilled man in matter of spectroscopy. That's why I put a lot of questions about.

 

[IsaacT]

Well subscribe. You may find a lot of answers.

 

[Pi R Squared]

I can't wait until we get to colors like "Cadmium Yellow", "Alizarin Crimson", "Cerulean Blue", "Burnt Sienna", "Raw Umber" etc. :crackup::crackup::crackup: This could go on for years!

 

[Teej]

The problem is multifaceted, as there are no universally correct answers.

Color is a subjective experience that is in the mind of the beholder...and cultural and experiential, as well as biological variables, will cause there to simply be a RANGE, rather than a "true" or "pure" color to exist.

So, as there are charts on Wiki, etc, that show what nm = what color, the ranges are there to google, etc.

It will be ranges though, due to the above variables.

After that, the polls are analogous to polls such as "What's the exact temperature for it to be a nice day?"

Now, if you are trying to see the RANGE, that sort of poll can be informative, but, by THEN only giving, say 4 choices, or 10, etc, you ask for what should be a range, in terms of specific data points.

IE: What's the exact temperature for it to be a nice day? Is it 65º, 67º or 73º F? (Pick one)


So, as Polls don't HURT anyone except Mr. Bandwidth, if you don't want to look, don't open the thread. (Being pointless, its less dangerous...)


We have NSFW in subjects, and, similarly, PC/T threads (Pure Color/True) do mention their topic, so, just like if you're at work and don't want to accidentally expose your screen to pole dancing pics, don't open threads that are labeled as PC/T polls unless you want your screen to display dancing color poll picks.

 

[Encap]

IT is none of those. Pure red is 685nm-690nm. Everything else looks red-orange in comparison. Also, I am tired of these threads as well.

I agree. These threads are a pain/annoying.

All monochromatic spectral wavelengths are "pure colors" by definition. Normal healthy eyes of someone in their 20s are capable of discerning about 150 different spectral colors--all of them different and "pure colors"

The main color wavelength ranges, depending upon which definition is used 6 or 7 colors, of the spectrum are the "spoken language spectrum".

The range of wavelengths of the "spoken language spectrum" called red is 620nm to 750nm well known, well established, and most areas within that range are not even listed as possible choices.

In reality, the spectrum is a continuum and a range of wavelength is associated with each of the monochromatic spectral colors and a myriad of visably district colors.
Some of these--example cyan (480nm to 520nm)--do not normally appear in the "spoken language spectrum" however they are very evident "pure color" bands when one looks at the continuum spectrum dispersed by a prism.

 

[BurningLaserGuy]

These threads are as annoying.

OK, OK... I'm sorry for making this thread and annoying so much LPF members. I wish I can go back in time and don't start this thread. I apologize.

Although, thanks to wannaburnstuff for making that awesome thread!

 

[zyxwv99]

This question has already been researched to death. It's 704nm, although older studies have it as 700nm, which is close enough. At that wavelength the R/G ratio is 15. That means the red cones are 15 times as stimulated as the green cones. (At these wavelengths the blue cones play no significant role.) At higher wavelengths the sensitivity of the green cones tapers off more slowly than that of the red cones, resulting in infrared color reversal. That's why an 808 looks the same as 660 and 980 looks the same as 642. In the high 1100s it looks like about 635, which is as high as it goes. At 1200 you'd need to shine a 30mW laser into your dark-adapted eye for 0.1 second to see the color, and that's just not recommended. In fact, 1140nm is the upper safe limit.

Above 632.8nm the cones are more sensitive than the rods. Color is maximally saturated "at threshold," i.e., the lowest brightness at which light can be seen, typically with eyes photopically dark-adapted for 10-20 minutes.

Those are the light levels at which these things are measured. Usually that's Newtonian (monochromiatic) light as opposed to Maxwellian (two colors combined such as red and green to produce yellow).\

There are also variations where a ring of white light surrounds the color disk, but that's to measure the effect of metamerism. For the color itself, they just go pure.

Also, this is foveal (center of the field of vision) either 1 or 2 degrees, with light coming from straight ahead.

 

[BurningLaserGuy]

At least now I have an very good answer. +rep for helping me.

EDIT: Oops! The rep button doesn't work.

 

[zyxwv99]

Thanks. Glad to be of help.

 

[zyxwv99]

Correction: according to many authorities, pure red is not a spectral color. At 704nm the R/G ratio is still 15, meaning the red cones are stimulated 15 times as much as the green cones. If you're talking about cone fundamentals, that would still be orange-red. On the other hand, the whole concept of a "unique" or "pure" color is entirely subjective, or "psychological" i.e., what test subjects report.

Adding a very small amount of blue seems to help, possibly by blocking yellow via the yellow-blue opponent process. Darker also helps, either because it puts green-cone stimulation below threshold, or because our brain automatically associates darkness with the ends of the spectrum.

 

[Lotus_Darkrose]

There's a new discussion thread for this topic, and people are still posting in these...and now you're double posting in this one. Let it go, and use wannaburnstuff's discussion thread please.

 

[zyxwv99]

These threads are valuable resources. Many people come to them years later for valuable information. They are not just for entertainment and idle discussion.

Just because some people have an issue, it doesn't make it my issue. After all, I run into these sorts of people all the time on Yahoo! Answers. They want to tell you about how the Rothschilds secretly control the entire world economy, then go on about the USS Liberty, the Lavon Affair, and the Five Dancing Israelis.

Sorry, but wavelengths and color are not a "forbidden topic." You do not own "these threads."

 

[Lotus_Darkrose]

These threads are valuable resources. Many people come to them years later for valuable information. They are not just for entertainment and idle discussion.

Just because some people have an issue, it doesn't make it my issue. After all, I run into these sorts of people all the time on Yahoo! Answers. They want to tell you about how the Rothschilds secretly control the entire world economy, then go on about the USS Liberty, the Lavon Affair, and the Five Dancing Israelis.

Sorry, but wavelengths and color are not a "forbidden topic." You do not own "these threads."

You are correct that I do not own these threads. Neither do you, or the person who created them really. The forum owns them I suppose.

My point, which I will re-iterate, is that there was a thread created to start putting all information and discussion into, to help get rid of the litter that these multiple threads create. And stop kidding yourself that they are all necessary. Separate poll threads for every single color? Get real.

Random foreign affair mentioning aside, These threads need to be locked. It's a discussion about one subject, wavelength. Just because there are many multiple wavelengths, does not mean there needs to be 5-10 threads about different colors that ask the same question. It's clutter.

 

[IsaacT]

Lotus_Darkrose hit the nail on the head. These are not the ypes of threads people will reference for years to come either. These are the questions only asked by new folks who haven't seen the wavelengths yet(typically, some exceptions). New folks are going to start a new poll. Like Lotus said: it is clutter.

Wavelength Photo/Verbal Comparison Thread
Wavelength Software Discussion Thread

The medium for this exploration exists. Just keep to a single thread.