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Old 05-13-2005, 03:39 AM   #16
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Quote:
Originally Posted by Ordibble P. Lop
If anyone is interested in scientific theories of image perception then this article on Image segmentation and light perception is applicable. It doesn't deal with colour but has similar optical illusions to the greyscale ones linked to above and a couple of videos.

I recently edited a paper that summarised the one linked above and it mentioned colour:

"The layers concept exemplifies a computational strategy known as inverse optics. The intensity at each point in the image is the product of a combination of factors: the proportion of light reflected by the surface at that location (called reflectance), the
intensity of illumination incident on that surface, and certain properties of the intervening
media, such as those of fog or filters. By the laws of optics these factors become entangled in the image. In principle they can be disentangled by hypothetical brain
processes that are inversely related to the optics of entanglement.

For example, a red book on the dashboard of your car casts a red reflection in the windshield. Through the reflection you perceive distant objects, including
green grass, in their normal colors. Light from the green grass and the red reflection physically mix to produce yellow. The yellow is observed when seen through a
small hole punched in a piece of cardboard held up so it blocks out the surrounding context. Without the cardboard, however, no yellow is seen, only the red and green
layers. The brain is thought to split the yellow light into the red and green layers using rules that invert the usual rules of color mixing. This is called scission."


Interesting stuff! I will *try* to read the articles after Master Servant

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Old 05-13-2005, 10:08 AM   #17
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to be honest i didn't get number 2
number 1 was trippy......
pretty crazy..
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Old 05-13-2005, 03:34 PM   #18
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Well......they're not jokes actually.

The second one illustrates how contrast increase has your rbain thinking that it should "reset" 50% grey in your head. At least that's how I get it.
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Old 05-13-2005, 03:53 PM   #19
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Quote:
Originally Posted by Lunatique
This is an excellent example of how colors are relative, and questions like "What's a good skin tone color to use?" are completely futile.


Absolutely! I've always maintained that colour choices are entirely relative. for instance, it is perfectly possible to produce a shot with a bright blue apple in it. in theory our brain tells us that a blue apple is weird/wrong/incorrect, but with colours in the surrounding space that work properly, relative to the blue apple, the entire shot can work perfectly (if a little weirdly). The movie 'Hero' is a very good example of this.

This stuff is fascinating to me.
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Old 05-13-2005, 04:22 PM   #20
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If anyone can produce a picture with a blue apple that looks red, I would be amazed. Not that I don't believe that it can't be done, just...it sounds so unreal.
 
Old 05-13-2005, 04:56 PM   #21
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Quote:
Originally Posted by paperclip
If anyone can produce a picture with a blue apple that looks red, I would be amazed. Not that I don't believe that it can't be done, just...it sounds so unreal.


it's not that the apple looks red - it's more that the image works as a whole, because the colour relationships work regardless of the subject matter.
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Old 05-13-2005, 05:38 PM   #22
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Quote:
Originally Posted by paperclip
If anyone can produce a picture with a blue apple that looks red, I would be amazed. Not that I don't believe that it can't be done, just...it sounds so unreal.


Ok, I've tried it, but it's far from perfect. But I think I got the trick, it works better if the surrounding colour is the opposite of (in this case) red, and perhaps if you have got some colour variance throughout the scene (which is not the case). Oh, well 10 min. wasted precious labor time!
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File Type: jpg apple.jpg (8.2 KB, 82 views)
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Old 05-13-2005, 06:07 PM   #23
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woah! my point has been totally taken out of context haha! interesting challange tho! far more interesting than my original point...

carry on!
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Old 05-13-2005, 08:27 PM   #24
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It looks more like a plum to me....let me see if I can do anything. Watch this space!(JUST the colors, remember, not the actual apple needs to be worked on, can you make a blue look red just by combining other colors? I bet Linda could do it!)
 
Old 05-13-2005, 08:50 PM   #25
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Why don't we all give it a shot? Seems a lot of fun. I'm going to try too.
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Old 05-13-2005, 10:29 PM   #26
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You know... if this thing gets popular, it might be pretty cool to see if we can come up with some mini challanges along the same lines.

I might have accidentally started a potential revolution!

Hey, I guess we should wait and see what people post, and if this thing really works 1st
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Old 05-13-2005, 10:37 PM   #27
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This is the closest I can get (for now )

 
Old 05-13-2005, 10:41 PM   #28
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Pretty cool. I've seen one of these before amazing how easily we can be fooled, guess the whole neutral and chromatic grays thing works in the same way.

weird...
 
Old 05-13-2005, 11:32 PM   #29
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'nuff said, but I'll keep trying. I went over the yellow border a wee bit. I cheated.This really is a good learning experience actually.
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Old 05-14-2005, 06:22 AM   #30
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Lightbulb

You've heard of the term that 'it's all relative' right?
That is how human find themselves.
How far apart we are from other ppl/things.
How can you tell a position of an object?

You tell it by the co-ordiated space in relations to others.

I think one green apple in a lone universe has no color at all actually.
Because you'll have nothing in which to judge it by.

As for this wonderful example of color perception?
Well, this is a good demonstration how we humans base are good at adapting.

Lets try and think of a system that human use exact color to percieve by.
And how confusing it is going to give us.

Hmm... That's an interesting thought indeed.
 
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