Colour Opposites

[MarkyP05]

I was once told as a young lad that colours have opposites ie red / blue white / black etc...they went on to say that we see the actual opposite colour but our brain changes it too the one that we see ourselves, is there any truth in this or the term that colours have opposites?

[smorodina]

I think you're talking about complementary colours - those that have the greatest contrast to one another. It's actually a complex topic, but generally speaking, the complementary of any primary colour is the mix or secondary produced by the other two. So Green is complemented by Magenta, Blue by Orange and Red by Cyan. If you stare at a coloured spot for a minute or so and then look at a white wall, you will see the complementary of the colour. You can do it with the red bar at the top of this topic. When you look to the white space at the left you can see an image of the block, but it appears cyan.

[gucciman]

in paint colour matching green is the opposite of red and yellow is the opposite of blue

[smorodina]

In fact, the complementary colours in subtractive mixing, that is pigment on paper, are the same as for light. The primary colours for pigments are magenta, cyan and yellow - not red, blue and yellow as is commonly thought. Look at the colours in your print cartridge and you will see this. there are some articles on these topics here:

http://en.wikipedia.org/wiki/Subtractive_color

[smorodina]

Mind you, yellow IS the complementary of blue. I have no idea why I put orange in my original answer!