Sciencemadness Discussion Board

color and iridescence

Yttrium2 - 13-3-2015 at 05:32

Remember the dress that was going around?
I thought maybe it was iridescent.

For iridescent objects, such as a dress that looks black from one angle, and blue from another, what is happening to the light? If only green light hit the iridesecent object what would happen?

vmelkon - 13-3-2015 at 06:58

You mean like satin
http://en.wikipedia.org/wiki/Satin

Probably it is like the thin film effect where some light wavelengths cancel each other or can't get out and some get into the surface and get out.

Yttrium2 - 13-3-2015 at 09:45

Can anyone elaborate on this?

Yttrium2 - 13-3-2015 at 10:29

Like sequin

nezza - 13-3-2015 at 12:58

Colour is produced by pigments which absorb light of certain wavelengths when illuminated by white light, for example grass absorbs red and blue so appears green. Iridescence is caused by microscopic anomalies on the surface of an object that interfere with light causing the rainbow effect you see with a cd or the metallic blue colours of morpho butterfly wings. Illuminated by green monochromatic light the butterfly wing would be black and the cd black and green in stripes.

battoussai114 - 14-3-2015 at 15:55

Quote: Originally posted by Yttrium2  
Can anyone elaborate on this?

This dress:


It's been around the web for a while and people have been arguing a lot if it's whether blue and black or white 'n gold. (though it's clear it's blue and black).

And no, it isn't iridescence the culprit. The theory I've accepted is that what happens seems to be related with the fact that the brain has color compensation just like video equipment. Based on clues on the ambient light the brain corrects the color you perceive so things look the same color under any type of lighting.
Due to the poor lightning and color balance on this photo each person brain is responsible for "reasoning" with the clues it has, and depending on what color your brain interpret as the one that was present on this scene when the picture was taken is what causes people to perceive different colors.
Due to this when the your

Metacelsus - 14-3-2015 at 16:26

What, you mean it's not blue and gold? :P

elementcollector1 - 14-3-2015 at 16:57

I definitely perceive gold, there's no way that top strip could be black.
Doesn't this also have something to do with how many cones you have in your eyes? Most people have three, some (like me) have four, and some have just two.

Etaoin Shrdlu - 14-3-2015 at 17:38

It's genuinely blue and black, that's the only color they made that dress in. Just a very poor picture.

I can't tell at all what it is just by looking, my brain flips between the two. If the dress is shadowed from the backlight it's white and gold/brown, if the front is lit too it's blue and black.

Morgan - 15-3-2015 at 06:21

I bought a linen shirt the other day that is sort of a khaki-light brown color with just a hint of straw color to it. In the house or outside in direct sunlight it looks uniform in color. But outside in indirect sunlight you can see a palm-sized spot about the 3rd button down that seems faded or where the dye didn't take. It's just very strange. Thanks Sri Lanka. ha

[Edited on 15-3-2015 by Morgan]