Rainbows to Iridescence

During the year of colour so many questions of visual colour perceptions of objects arose.
I avoided discussing the perception of colour as it has quite an ambiguous nature.

I slightly breached the topic for one post with the questionable colour of magenta, whether it should have been in the pink or purple month. I put in pink.

Not only the 'hard to categorize colours', raised questions of perceptions.
Objects made from transparent materials such as glass and plastic also were very hard to define.
It remained for me somehow unanswered and that it could not be completely defined in colour terms.

I wont fail to mention the great mystical question that also arose, what colour is the wind? And that was and is completely not definable in colour terms but is however definable within other physical properties.

And thats where I began to discover optical phenomenons, physical properties and our perceptions of them.

THE EYE ( a basic description)

When you look at an object, wavelengths of light from the object passes through the cornea, then the lens, and hits the retina at the back of the eye.

The lens of the eye acts like the lens in a camera. It focuses much of the light coming through the eye on to the macula. The macula is the part of the retina that is the most densely packed with seeing cells.

Nerve messages pass from the seeing cells (rods and cones) in the retina down nerve fibres in the optic nerve to the brain.

The messages are interpreted by the part of the brain called the occipital lobes, it is the primary visual cortex which enables us to see.

It is also the part of the brain where dreams come from.

So begins 2012 the year of the eye, topics in optics....

Optics is the branch of physics which involves the behavior and properties of light.

This all may be sounding quite scientific, but it resides more in a quote from Edgar Allan Poe....
"All that we see or seem is but a dream within a dream"

We begin with iridescence...

Iridescence: an optical phenomenon displaying a spectrum of colours that change due to interference and scattering as the observer's angle of view or the angle of illumination changes. It is defined under the umbrella of structural colors, colors caused by interference effects rather than by pigments.

It has a pearly, metallic quality.

Iridescent is derived in part from the greek work iris, a sweet-smelling flower and the symbol of the mythological character Iridos, the messenger of the ancient Greek gods. Iridos was the goddess of the rainbow, winging a message across the sky.

Optic topic (Iridescence):  Hematite; Oil and water on street pavement.