Can anyone explain this sun reflection in terms of angles?

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Discussion Overview

The discussion revolves around the physics of light reflection, particularly focusing on the reflection of sunlight on water surfaces. Participants explore how the agitation of water and its dispersive properties affect the appearance of the sun's reflection, especially in terms of angles and image formation.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant notes that the angle of incidence equals the angle of reflection on non-dispersive surfaces, questioning why the sun appears stretched across the ocean in a specific image.
  • Another participant suggests that the reflection observed is due to the agitation of the water, which may alter how sunlight is reflected.
  • A third participant points out that the reflection of sunlight on water surfaces facing away from the viewer is blocked more than those facing towards the viewer, potentially affecting the visibility of the sun's reflection.
  • Further elaboration indicates that a perfectly flat water surface would yield a singular reflection of the sun, while a rippled surface acts like multiple small mirrors reflecting light in various directions.
  • It is mentioned that the reflection intensity decreases as the angle of incidence reduces, with more intense reflections occurring near the horizon.

Areas of Agreement / Disagreement

Participants express differing views on the primary factors influencing the appearance of the sun's reflection on water. While some agree on the role of water agitation and surface characteristics, there is no consensus on the complete explanation of the phenomenon.

Contextual Notes

Participants acknowledge the complexity of the interaction between light and the water surface, including the effects of surface agitation and the angles of incidence and reflection. However, specific assumptions and definitions regarding these interactions remain unresolved.

WilkinzMicawber
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I'm trying to understand the physics of reflection to better draw objects. Normally, you see the reflection of a light source on metallic surfaces where the angle of incidence can equal the angle of reflection. This should reflect an image of the source that is approximately equal in size to how big the source looks from the point of view of the reflection surface, if the surface is non-dispersive. Why is it, then, that the sun stretches across the ocean so far in this pic? I know that water is dispersive, but i don't see how dispersion alone accounts for how far the sun is reflected.

I'm guessing it's explained by the agitation of the water.

http://www.wallpaperup.com/117114/landscape_sunset_sun_reflection.html
 
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http://farm7.staticflickr.com/6132/5916999452_9646f5f5cb_b.jpg

In this picture, you can see that the parts of the water facing away from the viewer reflect the sunlight from the position of the viewer up until where the sun would be reflected on unagitated water. Past this point in a direction, the sun is reflected on surfaces facing the viewer. Since surfaces facing away from the viewer are more blocked than those facing towards, more light comes from behind where the sun would be reflected on unagitated water. I believe this is the full explanation, no?
 
Forget for a moment the bright center lane of the reflection and focus on the edges. What do you see? Does it suggest an answer to your question?

EDIT: Ah. I see our posts crossed and you are getting it although I think the full picture is simply stated as just an effect of reflections off of an undulating surface.
 
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WilkinzMicawber said:
Since surfaces facing away from the viewer are more blocked than those facing towards,
I'm not sure what you mean by this comment.
WilkinzMicawber said:
I'm guessing it's explained by the agitation of the water.
Yes. If the water is perfectly (mirror) flat, there will be just one perfect of the Sun.
The randomly rippled surface of the water can be looked upon as a whole set of small plane mirrors at random angles; facets, if you like. 'Rays of light' from the Sun will strike all of these elemental mirrors. Rays will be reflected in all directions. Rays from each particular mirror in any particular area of the water will follow the laws of reflection and there will be some of those mirrors which will present a tiny image of the Sun to an observer. Most of the mirrors will send rays in a other directions - presenting images for observers in other directions. Whichever region of water the observer looks, he will see some reflected images in the water but there will be more facets that satisfy the condition for image formation along a line between the horizon just under the Sun and the observer. Paths off that line will produce fewer images and the result is the broad line which tails off on either side. Viewing the water with the Sun over you shoulder, there will be very few facets producing any image at all unless the water is very rough, with almost vertical sides to the waves. Also, the reflection coefficient also reduces considerably as the angle of incidence reduces - the most reflection being for a very oblique angle. (See this wiki link) so the reflection intensity is much higher near the horizon.
 
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