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Anonymous Poster

How Can We See Black Color

03/24/2008 1:32 AM

Dear friends,

As we know that an object appears white because it reflects all the visible light rays and an object appears black because it does not reflect any ray.

But my question is since black object does not reflect any ray it shouldn't be visible to us.But we can see it which means something is reflected from black object.. can some body explain how?

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#1

Re: How can we see black color

03/24/2008 2:02 AM

Can you define what 'visible' means ?

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#2

Re: How can we see black color

03/24/2008 4:59 AM

Hello Guest,

The answer to your question is: Yes, some body can explain how.

Kind Regards....

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#3

Re: How can we see black color

03/24/2008 6:46 AM

Easy peasy.

Black is NOT a colour it is the lack of colour.

You can not see black objects.

You can see everything around them, thus they become apparent.
It's a bit like a hole.... you can't see a hole, only the edge aound it.

If you can see it it isn't truly 'black' it may be very dark grey, blue etc, it may be slightly shiny... If it were really black then no light would get back to your eye and you couldn't see it.

Del

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#47
In reply to #3

Re: How can we see black color

03/25/2008 10:51 PM

Don't Cats see in the dark?

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#168
In reply to #47

Re: How can we see black color

04/09/2008 12:42 AM

Just cause I'm going over some old posts....NO, CATS DON'T SEE IN THE DARK...they just see in a larger spectrum of light than we do. That I am superior is just a human failing (ok, may be personal, but since I am obviously superior, I can't tell)

:P

And don't you dare mention the fact that I cannot see black, in any way dismisses Obama...he screws himself over so many ways I can't even begin to find the "black" issue.

Though, if I had my druthers...I'd shoot a random senator, and a random congressman. And then I would hope that others would follow my example. I'm gonna quit paying taxes for 08. Since govenment cannot responsibly spend them, I'm not going to give it to them. When the sherrif arrives a the gate, he can read the note and determine his next action. Enter and die. I can handle up to 20 apc's and 1, maybe two Abrams main battle tanks. After that, I die, but it should go up on youtube within minutes along with formulas and procedures for causing major chaos.

I can't stop them, and never thought I could. But a 10-20 ratio is easily attainable. Anything over that is just a bonus. Dying stupidly is absurd, dying stupidly for a cause is not.

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#169
In reply to #168

Re: How can we see black color

04/09/2008 1:37 AM

And just what did YOU eat (or perhaps drink) for supper to cause this massive puke of discontentment from an ordinarily non-violent bloke?

Mark

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#174
In reply to #169

Re: How can we see black color

04/09/2008 4:04 AM

Me, ordinarily non-violent? Just where did I go wrong in portraying my propensity for wishing to induce lead poisoning at high velocities to large numbers of people? Subtlety, thy name is not Tom. I believe, with certainty that the Founding Fathers of the US knew way more than our Faciest politicians of today. Problem is, the only way to stop them is to use kinetic lead imprinting technologies.

With almost absolute certainty, I'd be caught and more than likely killed, but I'm almost to a point that it would be a noble cause. Problem is, it's endemic in the system. Kill 1, or 10 or 100 and nothing would change. Cockroaches look to politicians as an evolutionary step.

I'm sorry if I appear a little jaded or bitter, but it has a tendency to surface, especially in any question or answer that I may find people relying on the excuse that some one else should fix/regulate/deal with the answer

Mark, I know you are a Canuck. I was born an American, and raised in London, ON. I have dual passports, and dual citizenship. What disgusts me about America is not even a consideration in Canada. It's called Fascism. Go look it up. Canadians have embraced it. Americans have been duped into it. What program, Canadian or American, can the government run better than the people can? Answer is none. You can be a toddler all your life if you want to, but I don't need you to tell me how to live. Do it in person and lose your trachea. I will feed it to you as you choke to death on your own blood while I hold it in my hand.

Freedom is the ability to soar and crash. You can chose to live well,. or die poorly. The government has no right or responsibility to tell you otherwise. People should be free to be stupid, and suffer the consequences. When the government decides to help poor, stupid people that don't work, they do it on my behalf. I don't want them to. They are stealing money from me to do things I don't wish them to. Steal from me, eat lead.

Find me a poor Politician. You can't. They are parasites living off of us. I'm just going to quit supplying them with blood so the leaches die. I've met one politician in my 43 year lifespan that I had respect for. The rest of them, I wouldn't feed to pigs.

Lets see, 3 sets of books (if I did that with my company, I'd be in prison), 45 TRILLION dollars in debt. And I'm supposed to trust or believe in these people? I quit paying them this year. They can come and try and collect. Death will abound. I will die, probably. So will tens or hundreds of people that work for the government.

I've met my state congressional rep personally. Mr Huntsman Jr. is a decent guy,he's not his father, but he has some of the traits and that makens him far and above most politicians I've met. I've told him I'm not going to let my government rape me. He, as you can probably understand, has some serious quandries with my attitudes. What he cannot (and to his credit) and did not attempt to refute were the reasons behind my attitude.

I no longer trust any politician to do the 'right thing' as I haven't met one who even knows what it is any more.

I don't ask them to help me, but I wont let them tell me who I have to help.

Life, Liberty and the persuit of happiness. That doesn't mean a good life, it means whatever life you can provide for yourself. If you fuck everything up and end up eating pizza crusts out of a garbage bin, that's what your choices have brought you to. No one owes you happiness, just you are allowed to persue it. Fail and that's your problem. Die and that's also your problem.

Our American Government should only do 3 things: Provide for the common defence, Promote general wellfare (not guarentee but promote), and lastly, secure the blessings of Liberty. Hence you are free to achieve your dreams...and free to fail miserably and die starving in squaller it that's all you know how to do.

If you've lead a decent life and things just went wrong, I may help you. I may not. It's not the government's decision to say who I help and who I don't. If I wish to leave you dying on the street, because I know you tried to rape my friend's sister, but the government just let you go on probation, I will let you die. If I know that you've been trying your entire life but things just never worked out, I will take you into my home and help you with all of my ability. But the government can't, nor shouldn't attempt to tell me who to help. But the govenment wants my money so they can help those that they think should be helped, but who I think are just a waste of oxygen. The government argues that I can't tell who is worthy of help. Bull shit. If I think they are worthy, they can have the shirt off my back. Ever see a politician go hungry? Not on your fucking life.

I'm not bitter, I just want to be left alone to make my own decisions. New Orleans paid taxes to keep the levies working...where the fuck did that money go? Levies died, hundreds of thousands of tax payers got fucked over. (not commenting on the stupidity of people building on a flood plain...doh, it's not called a FLOOD PLAIN for nothing)or. But government had no right to build and maintain those levees anyway. The people that wanted to live there should have been paying...and I bet if they were, the levees would never have broken.

Sorry, but I ramble, and I wouldn't run out of stories or opinions if I typed non-stop for a hundred years.

I'm working on taking my life back. I've got a bid in on a little 162 acre spread in south Texas. I'll raise my own beef, chicken and vegitables. I will take the entire complex off grid. I've been playing with and reading about enough crap to combine working elements and test some of my own designs on Stirling (Wally) engine designs. I'll have a compressed air energy storage cell as well a batteries and a plethora of energy collection devices.

I have the plans for my house and sub buildings all ready to go, and with 8' thick straw bale construction with a lead/concrete mid. Underground main lining and space. The only thing necessary is an above groud access corridor. After that gets done...come and get me.

Now, what was that you said about little ol' peace loving me?

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#175
In reply to #174

Re: How can we see black color

04/09/2008 4:23 AM

Oh my god!

Best way is to be a polititian and create polititians of similar thinking. The way you are following has no fruitful end.

Besides, I do not understand where from this subject came in original thread of seeing Black!!

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#178
In reply to #174

Re: How can we see black color

04/10/2008 1:35 AM

Most people are keeping quiet. Me? Hell, I'm stupid...

  1. So what made you think that CR4 was the appropriate forum to proclaim your reenactment of "Custer's Last Stand?!"
  2. It sounds as if this batch of back-woods Meth was especially good!!!
  3. Do you expect us all to be sympathetic?
  4. Good luck on the chicken farm in Texas!!! The chicken are probably already infiltrated by the Secret Service. So...
  5. Be paranoid! Very paranoid!!!
  6. Do all eunuchs think the same?!
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#179
In reply to #178

Re: How can we see black color

04/12/2008 8:50 PM

You get the Wooden Spoon Award, Vermin.

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#180
In reply to #179

Re: How can we see black color

04/13/2008 2:54 AM

My termites thank you.

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#181
In reply to #178

Re: How can we see black color

04/14/2008 11:04 PM

Just re, my beloved little Vermin

re 1: Sorry, but this little questioned turned political...not sure if I stared it, but I definitely embraced it. And what were Custers last words? "...where'd the heck did they get so many Indians?" Probably from the castle ARRRGGGGGGHHH (trails off)

re 2: No Meth, but the bathtub gin did taste kinda funny...ants, ants, all over my face...

re 3: Not for me, don't really care.

re 4 an 5: Crap! But I pity the poor Secret Service guy assigned to 'inserting' the transmitters.

re 6: Better than being Monique (bastage :P)

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#182
In reply to #181

Re: How can we see black color

04/16/2008 2:09 AM

When white man found this land, Indians ran it. No Taxes... No Debt... Plenty Buffalo... Plenty beaver! Women did most of the work. Medicine Man free! Indian men hunted and fished all the time! White man tried to improve it... Stupid White Man


But there is still plenty of bea........ Ummm, better not go there :P

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#183
In reply to #182

Re: How can we see black color

04/20/2008 10:11 PM

I think I might change the sig...I seem to be getting more comments on that than on my posts...and considering the contenciousness of my posts...that's saying something.

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#170
In reply to #168

Re: How can we see black color

04/09/2008 1:40 AM

Woo hoo hoo!!! Did you just spill stink on yourself!!!

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#176
In reply to #170

Re: How can we see black color

04/09/2008 10:23 AM

D'you suppose there's a country he can escape to for the purpose of avoiding the exception that proves the rule of "free speech" in his own country? Or the name of a really really really really good criminal lawyer well versed in constitutional law? Perhaps there's a computer in jail, so we won't miss his company.

Imagine! A country that prides itself for free speech, where you can be arrested for running off at the mouth to express your frustration just like in any third world country. Whatever happened to standing up in the bus to give your seat to an old lady?

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#177
In reply to #176

Re: How can we see black color

04/09/2008 3:32 PM

Although, it's a little like the yelling "theatre" at a fire thing.

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#172
In reply to #168

Re: How can we see black color

04/09/2008 1:50 AM

"Plenty beaver! Women did most of the work."

While I am not prepared to comment upon the juxtaposition of those two observations, it is quite apparent to me that there are still plenty of beaver, and that women still do most of the work.

Mark

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#184
In reply to #168

Re: How can we see black color

04/23/2008 3:03 PM

Don't know much about the cats thing, but concur with the rest whole heartedly. However, being a submarine officer, I prefer to confine myself to a submarine and let them come try and find me.

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#191
In reply to #184

Re: How can we see black color

04/29/2008 3:04 AM

Bad situation.

trapped in a long tube, surrounded by S...... oops

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#192
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Re: How can we see black color

04/29/2008 11:11 AM

Yeah yeah, I've heard them all before. Just remember, there are many more planes in the bottom of the ocean than there are submarines in the sky.... food for thought

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#193
In reply to #192

Re: How can we see black color

04/29/2008 12:23 PM

Yeah, but you keep tryin' (Emergency Blow)

http://www.usna.edu/Submarines/Images/emerblow.avi

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#194
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Re: How can we see black color

04/29/2008 12:40 PM

Woof ! I defy anyone not to get excited looking at that. I can almost smell that taste of the sea.........

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#195
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Re: How can we see black color

04/29/2008 12:48 PM

I think it was running from an amourous whale...you do know how whales get their jollies, don't you? They bite the tips off of submarines and suck the seamen out (rimshot please)

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#196
In reply to #195

Re: How can we see black color

04/29/2008 12:59 PM

Yes, these gags have done the rounds in the UK. Personally, I blame the Germans (we do that for most things in the UK), but those 'Crazy Germans' were always very good at that type of stuff.

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#197
In reply to #195

Re: How can we see black color

04/29/2008 1:32 PM

The only problem with your little phallic joke, is that even whales can't open up there mouths wide enough to get around our big tube!! Always remember, submariners do it deeper.

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#198
In reply to #197

Re: How can we see black color

04/29/2008 1:55 PM

Yes, but deeper where? Since you go down 100 men and come back up 50 couples.

(it's so nice to be back in an environment where someone actually gets the theraputic value in a good insult)

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#199
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Re: How can we see black color

04/29/2008 2:52 PM

only 50 couples until we break the surface, then it's 100 divorcees..... (I believe the submarine force actually defined (and/or created) insult therapy, we couldn't function without it)

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#200
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Re: How can we see black color

04/29/2008 11:17 PM

Us surfies have about the same divorce rate, but usually only after we cleared the forward chain locker of Philipino's (and got the requisit shots).

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#201
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Re: How can we see black color

04/29/2008 11:23 PM

There used to be a massage parlor close to where I live,... out the back was Siemens

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#203
In reply to #201

Re: How can we see black color

04/29/2008 11:57 PM

Damn it, I don't care what the genetic testing said...none of them were mine!

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#4

Re: How can we see black color

03/24/2008 8:28 AM

Or possibly the color black is not really black. Absensce of reflection is not black? As a photographer I was absorbed in this thought for a while. Shades of gray, allows us to see black. True black covers background colors.

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#5
In reply to #4

Re: How can we see black color

03/24/2008 9:20 AM

You could be onto something - what I see as 'orange', del might see as 'mauve' in my terms. Dels 'mauv'e could be my 'orange', and my 'mauve' could be del's 'orange'. It's just the name we give to a specific stimulus to our eyes. When we both look at a banana, we might be getting completely different brain exitement. I have no way of knowing if anyones neurons behave the same as mine when we all look at a banana.

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#23
In reply to #5

Re: How can we see black color

03/25/2008 7:06 AM

It may be true for banana, but when one sees a bottle of a wine, every body's neurons behave the same!

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#24
In reply to #5

Re: How can we see black color

03/25/2008 7:11 AM

Yes, you are right. What I look as orange, you may be looking as green (similar to what I see as green). But we are taught from childhood to identify and name those stimulus as the colors we call. Bit complex?

I may be sensing the leaves of tree in entirely different way than you. I may be looking leaves like Red as per your definition. But both of us are tought to say that sensing as green.

I have No way to know what you sense and you do not have way to sense what I see. !!

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#27
In reply to #24

Re: How can we see black color

03/25/2008 8:16 AM

Exactly ! It's almost like trying to compare how two people experience pain/smell/taste etc. No wonder I'm so confused.

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#79
In reply to #24

Re: How can we see black color

03/28/2008 9:43 AM

Color charts and sample print chip displays at paint stores seem to exhibit color intensity and hue progressions that "flow" smoothly from one color to another. If the green incorporating colors were interchanged with the orange incorporating colors, the displays would not flow.

Integrate that thought with the color frequency progression (radio waves) and that proves the order of color charts and displays is correct. Overall intensity levels could vary from person to person though.

That's the way I see it. Anyone know where I can buy ultraviolet house paint?

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#50
In reply to #5

Re: How can we see black color

03/26/2008 1:49 AM

Well, at least we all agree that bananas are round!

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#51
In reply to #50

Re: How can we see black color

03/26/2008 2:54 AM

How many sides does a banana have ? I don't have one handy, but they peel apart in several bits. I'm sure it's not four, that would sound silly. Even length-ways it doesn't have constant/infinite radius.

Hmmm, they do seem to have 4. I've never paused to study if different bananas have different numbers of skin sections.

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#171
In reply to #5

Re: How can we see black color

04/09/2008 1:46 AM

Sorry Kris, but that argument denotes an Oedipus complex or at the very least, Castration anxiety. Duck and cover boys.

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#173
In reply to #171

Re: How can we see black color

04/09/2008 3:53 AM

That took you a while to respond to - seems a little 'retentive', no ? I've no objection to what a grown man does with ducks in his own garden, but 'cover boys' ? 'Cover' is usually referred to as 'service' over here, and I can only guess that it's some allusion to a cottage industry. By-the-by, I'm a dainty Brit and always eat banana with a knife and fork. It saves my embarrassment at counting how many skins are formed by peeling one.

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#77
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Re: How can we see black color

03/28/2008 3:19 AM

Black is a term. It is a general consensus for our inability to see any color in it. It is an interpretation of our optical senses to a complete lack of any color. Hidden in it could be a bottle of wine, a wedge of cheese, or a bdsm scene with numerous British politicians or a Governor from New York.

True black covers nothing, and everything as it allows no color. It doesn't mean nothing is there, except to our tiny minds. Our visual range is minuscule. But remember, if there's no light and everything is black, I'm using a shotgun <evil malicious grin>

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#6

Re: How Can We See Black Color

03/24/2008 11:08 AM

go into a dark room. close your eyes. what do you see?


black.

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#7
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Re: How Can We See Black Color

03/24/2008 11:11 AM

Sort of purpley red squiggles and orangey spots and then I rub my eyes and I get this freakey paisley pattern than grows and shrinks and moves when I try and look at it...then my eyes hurt...

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#8
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Re: How Can We See Black Color

03/24/2008 11:14 AM

Rub harder - try salt.

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#22
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Re: How Can We See Black Color

03/25/2008 6:57 AM

Yes, we see somethings moving when eyes are closed even in dark room. It is noise of the eye, just like noise of any electronic instrument.

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#63
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Re: How Can We See Black Color

03/27/2008 4:59 PM

Everyone knows cats can see in the dark.....

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#97
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Re: How Can We See Black Color

03/29/2008 3:55 AM

And we people creat problems.... Not Einstein

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#99
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Re: How Can We See Black Color

03/29/2008 6:03 AM

Hey! SOMEbody must've created Einstein!

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#116
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Re: How Can We See Black Color

03/31/2008 11:04 AM

"And we people creat (sic) problems.... Not Einstein"

So you say, but Einstein created a problem for me in his challenge to understand his concepts. Hawking, Thorne and others have extended our understanding into the mysteries of the universe, time, space, and multidimensional realities all of which are based on Mr. Einstein's posits, but essentially we are still ignorant of the full meaning of E=MC2.

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#118
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Re: How Can We See Black Color

03/31/2008 11:37 AM

Well said!

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#125
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Re: How Can We See Black Color

03/31/2008 10:10 PM

No we're not!

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#134
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Re: How Can We See Black Color

04/01/2008 10:00 AM

Ahhhh Vermin, cute as you are I know you know what you know but I know what I know when you say you know what you know and that you know when you say you know then we both know and it'd be known to all who want to know when we know it is known to us to know that you know what you know and we'll wait until you let us know. You know?

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#139
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Re: How Can We See Black Color

04/01/2008 3:20 PM

See? I told you!

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#80
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Re: How Can We See Black Color

03/28/2008 9:50 AM

Love those flashbacks, especially when they're free. Makes me appreciate a good sneeze.

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#9

Re: How Can We See Black Color

03/24/2008 1:13 PM

And if you really think about it, we describe things all wrong... what we see as "green" is really Every Other Wavelength Except Green - Green being reflected back, all the others being absorbed... :) ( I know, it's semantics, but still interesting..) Thus, your lawn (if you have one) is every color except green, which pretty much accurately describes mine just now, too.

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#15
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Re: How Can We See Black Color

03/24/2008 11:37 PM

Uhm. Green doesn't get reflected, it gets absorbed. Every other color gets reflected. I think that's what you meant to say.

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#17
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Re: How Can We See Black Color

03/25/2008 12:55 AM

>>>>Uhm. Green doesn't get reflected, it gets absorbed. Every other color gets reflected. I think that's what you meant to say.<<<<

Pardon me, dracosilv, but I think JimatGodwinDowns was correct when he wrote that green objects reflect green light, while other colors are absorbed. If you consider it, what we "see" as colors is reflected light (originating from spectral photons emitted by the sun, and other light emitting devices). Colored objects are selective in what parts of the spectrum they reflect, and green plants reflect green light.

Regards.

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#142
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Re: How Can We See Black Color

04/01/2008 4:35 PM

Nuh-uh! The light that gets absorbed is what you DON'T see. You see only the reflected light.

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#10

Re: How Can We See Black Color

03/24/2008 1:25 PM

If we have a cave on a cliff face or a long tunnel the tunnel center appears black because there is no surface to reflect light. We see the tunnel as the surface surrounding the opening reflects light. In this case the reflected light is of the colors of the rocks or soils around the opening. In the case with a black object we see whats behind the object that light is obstructed from being reflected back to us. The object reflects no light so it appears black.

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#11

Re: How Can We See Black Color

03/24/2008 2:29 PM

Before I got too fat to squeeze through, I used to be a caver. When you get down about a click or so in a cave and turn off your light, you can't see anything, no matter how long you wait for your eyes to adjust. When there is no light reflected from something, that is what black looks like and it's invisible. If you can see something, it's not black. Maybe close, but not black.

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#12

Re: How Can We See Black Color

03/24/2008 4:03 PM

Interesting topic...

Have you all tried to understand the perception of black?

Look at your TV before switching it on... the phosphers give it a grey looking screen... Now turn it on and your eyes will interpret non-lit areas as dark blackish areas...

Even with no signal the screen appears darker when turned on because its a case of the eyes (or brains) fooling us...

John.

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#141
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Re: How Can We See Black Color

04/01/2008 4:11 PM

Have you ever tried to understand the perception of Japanese Urban Camouflage?

http://www.nytimes.com/2007/10/20/world/asia/20japan.html

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#13

Re: How Can We See Black Color

03/24/2008 11:09 PM

What is seeing? Is it being able to recognise with your eyes that the object exists? If so then a black object on a light background is seen, it is visualised, it is made apparent to you, despite the fact that no energy is reflected from it gives stimulus to your eye.

Take the newspaper for example, you read it, the print is visible to you because of the surrounding white paper which defines the edge of the black print.

On the otherhand if you look at a black object on a black background or try to see something in the pich black of midnight, it is invisible to you because you do not have and visual cues as to the extent of the object, nor of the existence of the object.(unless you have apriori knowledge from touching it or sensing it or seeing it previously)

Now what about dark matter in the universe?????

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#30
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Re: How Can We See Black Color

03/25/2008 11:50 AM

"On the otherhand if you look at a black object on a black background or try to see something in the pich black of midnight, it is invisible to you because you do not have and visual cues as to the extent of the object,..."

Suppose you have a large "green" object and you place a smaller "green" object in front of the larger one (both objects are the same shade of green). Wouldn't it also apply just as black objects would?

-John

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#14

Re: How Can We See Black Color

03/24/2008 11:15 PM

What we call black is not really black in the true definition. As has been mentioned above, if it were truly black you couldn't see it. So what we look at and call black is really only 90% black or some such number. There was recently an object that newly took the record for how close to black it actually was. True black absorbs all light. What is truly black is a black hole. It draws in all light in the visible spectrum allowing none to escape so it is truly black.

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#18
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Re: How Can We See Black Color

03/25/2008 12:56 AM

The colour of black is the state of matter or state of atom but black clour also reflects light partly while light fall on it. The black colour visible only when it is kept in light surrounded by clour reflecting surfaces in comparision(Relative object). Let us assume keep black clour object in dark room and you cannot see the object but you put the tourch light on the black object it will be visible in comparision with surrounded light reflecting surface. I will make still clear,In the same dark room keep the black object and surrounded surface shall be paint in dark colour and you cannot see the dark object but still you can see totally dark in colour as a single dark surface , it shows still black surface appearing means the black colour partly reflects light and definite dark object visible only in comparision with relative clour reflecting surfaces.

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#32
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Re: How Can We See Black Color

03/25/2008 1:47 PM

Hi, BIRADARMM !

Welcome to CR4. Have fun in here. Great first post!

Mark

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#16

Re: How Can We See Black Color

03/25/2008 12:45 AM

I didn't really read the question properly and failed to give the right answer in my last post. Here is the right answer:

Our brains can register a lack of light coming in through our corneas, because nothing stimulates our retinas and we call that "black." It's not that we can see black but we can't see it and our brain interprates it for us so we don't ask brain teezers.

Any "black" that we can see is not truly black, but almost black. It's like rounding off to black all those shades approaching black.

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#19

Re: How Can We See Black Color

03/25/2008 2:55 AM

Because there is no such thing as a perfect black - paint industry has been looking for one for some time, and there will also be some angular reflection (mirror). If the surface was flat then there would be no reflection (as per mirror) the best way to get the "nothing" effect is to look down into a drum of carbon black pigment and try to decide how far down the surface is! It is impossible, you are looking into a hole - no light can get back from the surface at the very bottom.

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#20

Re: How Can We See Black Color

03/25/2008 5:13 AM

As well as all the above, consider the surface texture. A gloss surface reflects light based upon its shape and the incident angle whereas a matt surface tends to scatter it more randomly, no matter what colour the surface happens to be. Further, the distance between the viewer and the object tends to alter the perception of colour; at a distance, colours are more muted and less intense than they are close-up, and no-one would be able to tell if the object ~600m away is painted gloss or matt. This is a feature of atmosphere and the background against which the object is viewed.

These issues give concern and anxiety to those who make scale models - paint the model the correct colour and sheen according to the prototype and it looks right in a glass case and wrong in a context! Mute the colours and surface textures, place the thing in context and it looks right, even though it would look wrong in a glass-case. Hmmmmmmmmmmm..........

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#21
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Re: How Can We See Black Color

03/25/2008 6:07 AM

Rice University, Houston, claim to have made the 'blackest black' yet using nanotubes. I don't care, because the phrase 'three times less' leaves me screaming. What's wrong with 'one third of'. Maybe 'black' is the same as albedo=0 ? Another rambling thought is maybe we could have 'Schroedinger's Banana' - is it black or yellow when inside the box. <slap>. That's better. These people might know an answer, with their talk of CIELAB metric.

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#39
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Re: How Can We See Black Color

03/25/2008 5:43 PM

Schroedinger was going to run the "Banana in the Box" experiment, but his cat (known as Deltoo) ate the banana. He had to find an alternate way to run his experiment, and Deltoo has not been seen since.

Bill

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#41
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Re: How Can We See Black Color

03/25/2008 6:05 PM

Deltoo's hasty eating probably got the better of him - it must be hard to prowl gracefully when you've got a banana-shaped body. He's surely going to pay a heavy price in the litter tray !

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#46
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Re: How Can We See Black Color

03/25/2008 10:43 PM

When will this be released in Car paint form?

And how does it interact with Radars :P

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#48
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Re: How Can We See Black Color

03/25/2008 11:25 PM

The area of discussion is visible light. Radar can still detect the car as it works on other wavelengths of Electromagnetic spectrum.

But, when this real black paint will come in car industry, you will see only driver and passengers travelling without envelop of car and surely will have accident immediately.

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#49
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Re: How Can We See Black Color

03/25/2008 11:30 PM

Might have more demand for Radar black paint than Visible light black paint...

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#52
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Re: How Can We See Black Color

03/26/2008 3:02 AM

Naughty, naughty ! I don't know if anyone has tried to build a true 'stealth' car, but Blink's '6000mpg' vehicle is fairly sleek, and still in development, so maybe he could be persuaded to add nanotubes.

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#82
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Re: How Can We See Black Color

03/28/2008 10:14 AM

Additionally, the black paint will warm the surface and the boundary layer, making the air of the boundary layer less dense and lowering drag.

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#84
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Re: How Can We See Black Color

03/28/2008 5:03 PM

It might be off-set by the sticky tyres as they heat up !

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#25

Re: How Can We See Black Color

03/25/2008 7:46 AM

why can we see a black "color?" Because we don't have a true black body type of paint. No matter what pigment you are using there is going to be some light reflected.

Painters use this to create a "warm" black by adding red to the black and a "cold" black by adding blue.

There was recently a new blackbody material created. Reference

http://www.rsc.org/chemistryworld/News/2007/March/01030701.asp

This would look rather black. Other than that you're going to see something.

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#26

Re: How Can We See Black Color

03/25/2008 8:05 AM

imagine yourself in ,say, Yellow color room with no shades.

Will u be able to differentiate between objects? No.

Shades define edges & indirectly surface.

Now, what are shades? they are nothing but presence of Black in the yellow. Depending on the position & intensity of light source they vary. Thus presence of Black reduces color intensity & the extreme of this is no intensity - no reflection - only Black. So, you actually don't see Black color, it is the absence of color intensity.

In black background u see White spot as it refletcs color & in white background you see black spot as white reflects color around black.

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#28

Re: How Can We See Black Color

03/25/2008 10:11 AM

We don't see complete black, but infer it by contrast against a visible background.

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#29

Re: How Can We See Black Color

03/25/2008 10:59 AM

You are right, in terms of language you can´t see black.

The answer is: to see is a verb commonly used in cases like this but the right one is "to percieve". Black is nothing but the absence of light or it´s refflection in objects wich can be "percived" because it does not stimulate the light sensitive cells in your eye´s retina as colors do so, what you percieve is the difference in the stimulation they cause.

"Using the right words allways helps understanding!.

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#31

Re: How Can We See Black Color

03/25/2008 1:41 PM

Hi, Guest!

White is the combination of all the primary colours. Black is the combination of all the secondary colours.

Mark

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#33

Re: How Can We See Black Color

03/25/2008 3:29 PM

Depending on the reference system you are using, additive or subtractive, white can be all colors or black can be all colors.

In light if you put all the colors of the rainbow together you get white. (addition)

In pigments if you put all the colors together you get black. (subtraction)

You see black objects because the suroundings are not the same color and nothing in real everyday life absorbs perfectly all colors.

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#34
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Re: How Can We See Black Color

03/25/2008 5:00 PM

"...and nothing in real everyday life absorbs perfectly all colors."

This stuff may be getting close though.

-John

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#36
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Re: How Can We See Black Color

03/25/2008 5:12 PM

Nobody read my #21.

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#38
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Re: How Can We See Black Color

03/25/2008 5:34 PM

I did...

I've seen this on Photonics.com too (Photonics Spectra magazine)

Other nano processes wil yeild the whitest of surfaces

Neither does come close to my mind, at times...

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#40
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Re: How Can We See Black Color

03/25/2008 5:58 PM

My God, you've electrocuted vermin !

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#42
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Re: How Can We See Black Color

03/25/2008 6:22 PM

No! It's just a phase change nanoVermin

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#43
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Re: How Can We See Black Color

03/25/2008 6:43 PM

LOL ! It's the kind of demise he'd like.

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#44
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Re: How Can We See Black Color

03/25/2008 8:27 PM

Humble apologies Kris. I didn't engage my eyes before putting post in gear.

-John

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#45
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Re: How Can We See Black Color

03/25/2008 9:01 PM

It's cool johnhohn - I was looking for sympathy votes !

Kris (dashing in and out......)

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#35

Re: How Can We See Black Color

03/25/2008 5:03 PM

A little different twist. As an artist this question is asked quite often in art school by freshman because of the requirement of mixing paint. The answer is that you are not seeing "true" black, but shades of grey because the absence of all light is when there is true blackness. Even straight "black" out of the paint tube is not really black, but we were counselled by instructors not to use "black" out of the tube anyway.

Interesting references about darkness and light: Matthew 25:29-31 and Revelation 21:23

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#37

Re: How Can We See Black Color

03/25/2008 5:19 PM

"BLACK" is how your brain interprets no light thus no impulses from the optic nerve. Close your eyes and put your hands over them. We know that both your eye lids and your hands have color, but there is no light... so you see "black".

Bill

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#53
In reply to #37

Re: How Can We See Black Color

03/26/2008 2:14 PM

Exactly ... What we know as black color is the null light input through our optic nerve...


Thus if an object is not reflecting light .... the no-signal in our brain is interpreted as "black"

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#54
In reply to #53

Re: How Can We See Black Color

03/26/2008 10:59 PM

Hello jfmart

On the basis of your statement, a totally blind person just sees darkness.

Kind Regards....

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#55
In reply to #54

Re: How Can We See Black Color

03/26/2008 11:12 PM

Is it really so? I do not think so. Some Neurologist should comment here.

Reason why I do not believe is simple. Even if we close the eyes or go in real dark room, still we do not see it as total black, because of the noise in our neuro system. Still we see something grayish, something moving around ... sort of small worms.

Doesn't blind person have this noise? I am not sure.

Any Neuroscientist there ?

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#56
In reply to #55

Re: How Can We See Black Color

03/26/2008 11:42 PM

I have no expertise per say, but I thing it would depend on the type of blindness one has.

Noise could come from different places in the signal chain, from the eye to the visual cortex, and on.

Also, there is some remanence of the visual signal that may cause some artifacts you are seeing, to lessen over time.

Darkness is a relative perception, quite influenced by thought and memory, from my experience doing darkroom work. Not to mention by other senses.

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