The Physics and Psychology of Colour - with Andrew Hanson

Our experience of colour is a based on the physics of light, but Andrew Hanson uses demos and optical illusions to show that there is a lot more to colour than meets the eye.
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Colour informs, influences consumer choices, warns us and comforts us. But how do we ascribe numbers to a human perception which is incredibly versatile and variable? Andrew Hanson will elaborate on his own work in the field of colour measurement.
For 25 years Andrew Hanson has been professionally measuring colour, from evaluating the appearance of ornamental plants, to building the world’s first national standards telespectroradiometer to calibrate the colour of visual display units and a machine to measure the shininess of cats. He is currently Outreach Manager and Occasional Senior Scientist at the National Physical Laboratory, the UK’s National Measurement Institute and is past Chairman of the Colour Group of Great Britain.
This talk was filmed in the Ri on 19 March 2018.
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[@DANGJOS]

Literally the most fascinating talk I've listened to on here!

[@RainbowDevourer]

Yes, color and light and stuff. Can we talk about that fabulous jacket and shirt now? (I did watch the video and found it compelling, for the record)

[@ridealone7933]

RainbowDevourer, Lol! I was thinking the same thing.

[@fburton8]

Yes, what colour is that shirt??

[@opalhopeful9626]

LoL! IKR? I see GOLD in that shirt. Fabulous!🌟

[@JonesP77]

In the beginning it looks a little bit weird, but after all, its a good looking jacket and shirt. It seems like something only people with blue blood would have.

[@opalhopeful9626]

PP I would have that shirt in a heartbeat. I'm blue but I don't know about the blood until further laboratory tests. I'll let you know. ;)

[@mathisawesome618]

Wow really cool way of connecting the start and end of the presentation and wrapping it all up

[@danielplainview2584]

Brilliant talk. Love that we can share this information via the internet.

[@avionicstechshop7664]

Well, that was a colorful presentation.

[@holdmybeer]

boo

[@avionicstechshop7664]

holdmybeer LOL, I guess it's all psychological.

[@avionicstechshop7664]

Jo A Well, if you can't laugh at yourself. Right you are. Thanks for the spellcheck.

[@jasp9661]

That was an amazing presentation, very well done - good job!

[@peymanali922]

Very fascinating discussion. Thank you so much for your insight.

[@mgurney88]

Fantastic lesson Andrew! Thank you for sharing.

[@MN-sc9qs]

The orange and grape illusion is amazing!

[@andreaswagner6022]

loved this one

[@RUFeelin]

Just brilliant. I want more. Where is part two!!!

[@NathanOkun]

Actually, he only talked about a small part of this mind-sensor mess. What your eyes see can change what your ears hear! This is how ventriloquists do their thing. You see their own mouths very still, but the puppet's mouth moving a lot, so your brain automatically moves the center of your hearing system to the puppet. This can even change the sounds that you think you hear, since a human mouth makes certain sounds when moving certain ways, so your brain will sometimes overlay the actual sounds with those sounds that it thinks that the mouth moving like that HAS TO have generated; that is, you get two different sounds when you open or close your eyes when staring at a talking face with the audio portion of the image different from the video portion of the image -- AND YOU CAN'T FIX THIS!! This can create some very scary effects that make you think you have gone crazy.

[@happilyevernever4289]

And there's this illusion in youtube where there's this list of words on screen, plus a word that is uttered repeatedly. Whichever word you read from the screen is what you actually hear. It's crazy.

[@NathanOkun]

@@happilyevernever4289 Hadn't seen that before, but it fits. You can be so easily manipulated if the person doing it knows his stuff...

[@keisi1574]

@@NathanOkun I appreciate your input here...The human brain/mind is easily manipulated- in a variety of ways. That's why so many people have so many beliefs which are actually have a foundation in them being tricked, fooled n manipulated. It takes awareness n focus n conscious consistent effort to guard against the various purposesful manipulations and or misinterpretation(s) and or misunderstanding(s).

[@vgfxworks]

brilliant!

[@beanyume]

Very nice video!

[@anoushkapatel6809]

great vid cant wait for more content :))))))

[@TheRoyalInstitution]

Well you're in luck, we release 2-3 videos every week.

[@flavioryu5922]

wow, im impressed

[@luvisacigarette8]

Fantastic talk; fantastic speaker. Does anyone know if there was a Q&A for this session? I couldn't locate it on youtube :(

[@TheRoyalInstitution]

There was only time for a single very brief question after this talk so we decided not to put out a separate video.

[@DANGJOS]

@@TheRoyalInstitution You should post it anyway. People may be interested. If you can, that is.

[@jennief2108]

Thank you ...........)

[@wompstopm123]

19:20 IMPERIAL DEMON I WILL NOT FALL FOR YOUR TRICKERY

[@saurabhverma7366]

what you know influences what you are seeing.

[@xmoreno3366]

Awesome Really Love it ❤️❤️❤️✨✨✨✨✨✨👍👍👍👍👍👍 I'm beginner in Visual Draw Hobby Thanks My New Fav Video about Color.

[@necksugar]

Depends on the light or shade thrown onto it.

[@cogen7996]

real science here, thanks ! ! !

[@PM-gp5pq]

Reading Goethe and Werner while complementing Berger's Ways of Seeing with this wonderful lecture, the timing couldn't have been more colourful

[@TheNefari]

Whan an eye opener :D

[@DANGJOS]

I see what you did there

[@fungas4804]

people often ask me "then how do you see traffic lights" and I answer, half jokingly "red is at the top" - maybe there's more to that than I first thought...

[@HarryNicNicholas]

my ex wife is japanese and she swears that green is blue.

[@Alkis05]

@@HarryNicNicholas I don't speak japanese, but people from different cultures often classify color different. Homer in the Illiad uses the word purple to describe the color of the sea. And he says it is wine looking. Since the traffic light is a closer to the cyan side of green, maybe there is something to that.

[@ClarisseRobles]

Awesome video! But shouldn’t It be Red, green, and blue cones we have in the human eye and not yellow, green, and blue as shown in the video? Or Can someone please explain this to me better.

[@lakshmanankomathmanalath]

Great!

[@xmoreno3366]

THANKSSSS THANKS THANKS THANKS

[@orange42]

"Beyond the 2 degrees there is not that much sensitivity" although Psych 101 courses have students showing there is certainly enough sensitivity to determine between colours in peripheral vision at 30-50 degrees.

[@fburton8]

Dan Dennett has stated this too. I believe the claims of colour insensitivity in peripheral vision are exaggerated. I can tell what colour an object is that enters at the edge of my visual field without having to look directly at it.

[@JC_923]

@fburton8 That is hardly good enough to conclude that you can detect colour well at the edge of your visual field. Even when a banana isn't yellow, we think it's yellow. The brain fills in the gap a lot of the time without us realising it.

[@fburton8]

@GG TT It would be good enough if the test was done properly under laboratory conditions. I was trying this out the other day while walking round the campus and seeing people wearing coloured clothing and objects such as cars, flowers and poster signs come into my peripheral vision. Most did not have easily predictable colours, unlike a banana, yet I could see the predominant colour correctly in most cases. It is certainly true that the colours are not nearly as rich or diverse as those of direct vision, but basic colours were visible. Assuming the experiment has been done, maybe it needs to be repeated with more subjects given that people's visual abilities differ.

[@dsu7]

Hey I have one question . What would have happened if there would have been an another living being , with eyes whose visual cortex would be working differently to perceive colour but in the same range as ours .then would his colour perception would be same as ours ?

[@juliussulit3306]

We can’t even know if how you perceive the color red is the same as how I perceive it. Perception is private and only produced in our own individual brains. Also, you can’t describe colors except referring to objects having those colors. If, theoretically, we perceive colors in a complementary way (e.g. you perceive red as your red, but I perceive my red as your cyan), we would still agree that the color of the stop light is red because we have always associated the term red for that color, even if we perceive them differently. But again, the beauty is we will never find out.

[@kavorka8855]

interesting!

[@System32Frag]

I'm have always been confused with the 2 degree of color vision thing! I see colors perfectly good basically all the way to the edge of my field of vision, I have tested it out in so many ways, Have I got good vision better than most?

[@James-jb7ow]

How have you tested it? It is possible to test whether you can truly distinguish colors on the edge of your vision but generally speaking the peripheral lack of color is imperceptible because your brain compensates and fills in the details, similar to how your nose is constantly in your field of vision but your brain ignores it, or how your brain vertically flips the image that’s hitting your eye 180 degrees.

[@ginatinyverge9661]

Fabulous talk!

[@cidfacetious3722]

Who chose that camera angle at 27 minutes I wanted to participate

[@thanawitsagulthang6471]

even at that camera angle the effect is enough for you to perceive, I already tried that myself.

[@cidfacetious3722]

thanawit sagulthang don't tell me what I can and can't 😗

[@nomadpurple6154]

CD....I think that example needs updating :)

[@DonaldSleightholme]

if you have a white led made from blue and yellow phosphorus phosphate does that light split into blue and yellow or all rainbow colour ? 🌈 🤔🤷‍♂️

[@louisasabrinasusienehalver2396]

On both of the "stare at the tiny cross in the middle of an object" experiments...i saw nothing but black.. with both, my eyes shut and open! What does this mean?

[@JanisFroehlig]

Do you suppose we do the same perceptive "morphing" of ideas? Of political thought?

[@sntk1]

Schrödinger: If you ask a physicist what is his idea of yellow light, he will tell you that it is transversal electromagnetic waves of wavelength in the neighborhood of 590 millimicrons. If you ask him: But where does yellow come in? he will say: In my picture not at all, but these kinds of vibrations, when they hit the retina of a healthy eye, give the person whose eye it is the sensation of yellow. Weyl: Thus the colors with their various qualities and intensities fulfill the axioms of vector geometry if addition is interpreted as mixing; consequently, projective geometry applies to the color qualities. Warnick & Selfridge: The laws of electromagnetic field theory as expressed by James Clerk Maxwell in the mid 1800’s required dozens of equations. Vector analysis offered a more convenient tool for working with EM theory than earlier methods. Tensor analysis is in turn more concise and general, but is too abstract to give students a conceptual understanding of EM theory. Weyl and Poincaré expressed Maxwell’s laws using differential forms early this century. Applied to electromagnetics, differential forms combine much of the generality of tensors with the simplicity and concrete- ness of vectors. Where are we? Vectors are *dual* to differential forms. A simple form has the dimensions of area. And what we see are colored areas. Poynting's vector gives us the energy flux thru an area. Energy is related to the frequency of light by E = hv. Looking at the frequency, we can read off the associated color. This is a far more satisfactory picture than the usual one found in many accounts, where color is loosely identified with frequency. But this putative identity fails a basic test of dimensional analysis. A frequency is a scalar, being a simple rate. And so with wavelength. Whereas color behaves like a vector. Weyl said so, just now. Maxwell, Feynman, Riemann and Grassmann concur. And this is how electrical engineers work with colors (and sounds) when devising display screens for TVs, phones, and so on, giving us a trillion-dollar proof of principle.

[@j.m.dirassar]

At 19:45 he calls the green bars "blue", which I know is correct for some people, it just amused me coming from someone like Dr Hanson himself

[@Radonatos]

Interesting - I perceive them as blue, maybe more like cyan (which means it has blue and green in it), but still more on the blue-ish side. Might as well be slight differences in the color calibration of our screens - did you see the bars as red in the (inverted) after-image?

[@j.m.dirassar]

Radonatos it could be, yes... I saw Union Jack bright and clear, so I guess if the navy blue came out of the yellow areas, the red colour should've come out of green (actually cyan, I agree) but maybe it is a cultural difference, since my mother language is Spanish and we consider only darker tones of blue as actual blue, calling lighter tones "celeste", i.e. sky blue, celestial blue... so for instance the famous japanese traffic lights are not considered blue in Spanish, but "celeste"

[@James-jb7ow]

It’s cyan which is right between the green and blue wavelength so people are gonna side differently. I consider cyan blue

[@khizzard_069]

I didn't understand the last part 😕

[@yecto1332]

Good with the presentation with one person in the audience who is colour blind

[@nefdsnet]

Londo Mollari approved outfit. Missing the traditional crest though...

[@AbdulAbdul-qp4yo]

❤❤❤

[@D43123]

I was dazzled when he said James I was thinking m is that you

[@jabum3359]

5:00

[@eddiemorrone870]

That yellow object looked green under blue light.

[@allpraisetothemosthighyah]

Purple

[@abiodunbabatunde2832]

I have

[@NetAndyCz]

No way those eyes at the end are identical.

[@rkpetry]

*_...and then there's 'sterling' consisting of finely alternated stripes like shimmering silver..._*

[@JK-vc5vu]

Raymond K Petry .. do you always show up with your own yellow paint striping truck and divert peoples minds by force, because I’m off in the weeds thinking about your comment. (Compliments to you).

[@Venusian1]

I always saw it as 'color'

[@holdmybeer]

I think 'color' is the USA way of spelling it. heres what google says "Color and colour are different spellings of the same word. Color is the preferred spelling in American English, and colour is preferred in all other main varieties of English." (whatever that means?)

[@bytefu]

Well, that obviously means not USA varieties, such as Australian, British and so on. The word came from French and is originally written as "colour".

[@ZeedijkMike]

+holdmybeer : In AutoCAD (a drawing program) you can use both Colour and Color. I always found that a neat feature.

[@j.m.dirassar]

Dr Hanson actually cites two works around 32:40 one named with using "colour" and the other one using "color", pressumably from UK and USA, I guess

[@ophiolatreia93]

Monster energy is using the peaceful colour?

[@LordZordid]

Regarding the dress. Most people saw the same image. I saw two distinctively different images. I assume it's the brain who sorta blurs the colors out so they appear to be the same image.

[@LordZordid]

For instance. To me this picture consist of three different colors (gold and satin) + (light blue and black)+(dark blue and black) How do you percieve it? www.playbuzz.com/lailah10/what-color-is-the-dress

[@alangrant9451]

An accurate title would be “The Science Behind Seeing Color” This had nothing to do with the psychology behind colors, and sadly that’s the whole reason why I wanted to see this presentation.

[@realcygnus]

@ the very end, the 4 colors are NOT identical.

[@bonob0123]

yes but he showed how by changing the context he could get you to confuse each of them for another. Its a tongue in cheek comment

[@spoddie]

You need to stop using these close mics, it sounds like he's chewing gum in our ear. Use lapel mics.

[@hunzilah]

if a red strawberry absorbs every wavelength except red and then re emit them after just a nano second then why is the strawberry not white

[@KGOVINDADITYA]

because the red light is what our eyes recieve after getting bounced off of the strawberry's surface....so i think.

[@johndavies9589]

Sorry to be picky but accuracy is important - the negative Union Flag wasn't blue black and yellow, it was cyan black and yellow. Cyan is the complementary or red - common 'blue' isn't.

[@ophiolatreia93]

Louid XIV wants his clothes back

[@achatinaslak742]

What? Corona aureole? Corona has no aureole, it has spikes ! Oh wait...it is May 2020 now!

[@Divchyk]

Colour is not crazy it's all in our perception. Good start of presentation, but fuzzy ending. Bunch of examples without clear conclusion proposition. "The way we see colour varies with light level a lot..." Wow...Who did not know that - raise your hand please ) After all this, one may say ok, so what? It may impress people who know very little about brain work or psychology. My point is that the speaker failed to show how it mattes whether colours are the same on different parts of the picture, etc. We make our decisions in life not based on pure logic (despite our own conviction at the decisive moment), but on perception and conditioning we received in childhood and during some emotionally-charged situations later in life. I grew up in a rural environment with very natural colours around me, so even now I never buy brightly coloured sweets or food in "good mood" colored packaging because it is associated with artificial, chemical, poisonous that one should not put inside the body. However, kids who grew up with all that around since they were born may associate bright blue, purple or orange with icing on cakes, certain holidays etc. If someone had very bad experience from a person dressed in a certain positive colour, subconsciously that person would avoid that colour etc.

[@procactus9109]

He needs more people to study, Both of my eyes have very good peripheral vision in full colour. I can recognise random shapes and colour without looking directly at the object.

[@69sexo]

Nice outfit

[@TronSAHeroXYZ]

Color or Colour?

[@sheeshramteke7879]

CK'sGaming Channel both are correct

[@wifighostcruiser9665]

Never mind how we see color, I'm still trying to figure out how you spell it LOL

[@happilyevernever4289]

Color in America. Colour in Britain.

[@zacharysancartier3454]

great. I'm color blind and also don't know shit. Lol

[@ridealone7933]

NIST > NPL

[@macaronisalad11]

Photoshopped.

[@Doc_Fartens]

I don't like that he implies the moon is a source of light, rather than just something that reflects the Sun's light.

[@ridealone7933]

Ryan, that’s because he is from NPL and not NIST.

[@IngieKerr]

I understand your thought here, however the moon _is_ a source of light. The light from the sun exchanges its energy at the quantum level when it hits the atoms of the moon's surface, then photons are emitted from the moon due to being pumped by this energy. Sure, it's not a primary source, but in the context of the real physics in the main, and specifically of light here, that's not relevant unless one is discussing how those quantum events may therefore change the colour/other discreet properties of the incoming sunlight. That's not meant to sound pedantic or preachy at all, simply a reflection (no pun intended) of how our day-to-day language of macro-scale physics, often clouds the weird way nature actually is :)

[@fluxpistol3608]

Can the source be relative to the spectral filter?

[@KuraIthys]

That destinction is really rather dubious anyway. Everything that is visible is by definition a source of light. Even if it's reflecting it from something else, chances are it's actually absorbing and then re-radiating the light.

[@wilband]

what a pedantic point to be bothered by. obviously an irrelevant distinction in this context.

[@JustOneAsbesto]

That outfit. Does he know he's not Indian?

[@zertxer_zertxer]

It's quite okay. Indians wear suits too, sharing culture is wonderful.

[@lessandra602]

i think his wife maybe

[@dianadamin]

Maybe you're seeing too much color after his brilliant presentation :)

[@red-eyedmagister1595]

what's with the jacket and shirt? is this how they dress in England?

[@nomadpurple6154]

does everyone in the US wear hats like Lincoln?

[@amiera1233]

@@nomadpurple6154 yeah

[@codeman7055]

Probably not a good idea to buy future clothes like what if she ends up eating McDonald's and then she couldn't wear it,

[@Wandorlive]

faker

[@lolgamez9171]

So sad no one laughed at his carrot joke

[@alfred3009]

Color*

[@LordZordid]

I always write it as color to please the majority.

[@DANGJOS]

@@joa8227 Both are correct in their respective countries. Language evolves all the time.

[@nomadpurple6154]

@@LordZordid The majority of where though. Indians seem to use British English & there's 1.4 billion people !!!

[@LordZordid]

​@@nomadpurple6154 First of all you necro a two year old thread which is not cool. Second of all most people will assume I use social media specific to my culture hence my statement. Third and foremost I could have been specific, but most people would also assume that my statement is used to avoid dealing with this non-issues. Thank you for wasting my time. It's been a real treat.

[@onebylandtwoifbysearunifby5475]

@@LordZordid He's right though, there are more people in India. U.S. is only 4.25% of global population. Majority of the world do spell it "colour". Even half way through 2022. But i will update you in 5 years if that changes. 'Till then...

[@michaelmacdonald2907]

Bored for the first 15 min. Old stuff explained better by everyone else. Didn't improve from there. Only interesting to (British) highschool students. And I was really hoping he would contribute something . . something.

[@i-m-alien]

bcoz u do irritating drama so , now i understand why one community is killing you people.....when ur educating the people then dont do double work , only be on topic of education

[@cidfacetious3722]

Lame

[@dworkeen]

Jay Gunter Hey Jay, what an amazingly perceptive critique. So clever.

[@cidfacetious3722]

Lew Hunt thank you, you could say a lot with just one word;)

[@dworkeen]

Jay Gunter Gosh, how confusing. I don't which one of us is the more sarcastic. Touché

[@cidfacetious3722]

Lew Hunt I think we just became best friends