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Double Rainbow
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Photo Information |
Copyright: Frederic Ng (airwaves78) (30) |
Genre: Landscapes |
Medium: Color |
Date Taken: 2006 |
Categories: Sky |
Camera: HP Photosmart M407 |
Photo Version: Original Version |
Date Submitted: 2006-12-29 3:50 |
Viewed: 31814 |
Favorites: 1 [view] |
Points: 14 |
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[Note Guidelines] Photographer's Note |
Here's a panoramic view of a double rainbow. It's made up of 3 pictures using Autostitch. Unfortunately, I didn't get the second rainbow completely.
I see that there's a link for panoramic pictures. How do we do to post pictures there?
I found the following explanation about double rainbows:
What makes a double rainbow?
Sometimes we see two rainbows at once, what causes this? We have followed the path of a ray of sunlight as it enters and is reflected inside the raindrop. But not all of the energy of the ray escapes the raindrop after it is reflected once. A part of the ray is reflected again and travels along inside the drop to emerge from the drop. The rainbow we normally see is called the primary rainbow and is produced by one internal reflection; the secondary rainbow arises from two internal reflections and the rays exit the drop at an angle of 50 degrees° rather than the 42°degrees for the red primary bow. Blue light emerges at an even larger angle of 53 degrees°. his effect produces a secondary rainbow that has its colors reversed compared to the primary.
It is possible for light to be reflected more than twice within a raindrop, and one can calculate where the higher order rainbows might be seen; but these are never seen in normal circumstances.
Why is the sky brighter inside a rainbow?
Notice the contrast between the sky inside the arc and outside it. When one studies the refraction of sunlight on a raindrop one finds that there are many rays emerging at angles smaller than the rainbow ray, but essentially no light from single internal reflections at angles greater than this ray. Thus there is a lot of light within the bow, and very little beyond it. Because this light is a mix of all the rainbow colors, it is white. In the case of the secondary rainbow, the rainbow ray is the smallest angle and there are many rays emerging at angles greater than this one. Therefore the two bows combine to define a dark region between them - called Alexander's Dark Band, in honor of Alexander of Aphrodisias who discussed it some 1800 years ago!
Source: The National Center for Atmospheric Research
http://www.eo.ucar.edu/rainbows/ |
Janice, kojak, horia, marjan, MarieAnge, ffrank007 has marked this note useful Only registered TrekNature members may rate photo notes. |
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bonjour frederic
très belle photo on a l'inpresion que la monagne est prise dans une bulle j'aime beaucoup
- Janice
(18832) - [2006-12-29 4:49]
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Hello Frederic, hurrah, you posted your rainbow today. It is a good show of nearly the whole of the rainbow - you sewed it together very well.
The sky does seem to be a little too blue though - too much saturation I think. But still a good capture, and thank you for sharing,
Janice
- kojak
(163) - [2006-12-29 5:45]
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Very special picture indeed! You caught a pretty decisive moment, very unique that double rainbow.
I guess I agree with Janice on this: a little bit oversaturated, but very good composed!
Congrats,
Geert.
- horia
(16656) - [2006-12-29 6:27]
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Hi Frederic
What a magnificet phenomenon and what a splendid photo!
I don't think words are enough to describe such beauty...
The stitch between the 3 photos is impeccable, the colors everywhere are most impressive and charming and the POV is excellent.
Truly a magical post!
BRAVO and TFS
Horia
- marjan
(2685) - [2006-12-29 11:19]
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good shot and interesting moment of this fenomem.
Marjan
- mdt (38)
- [2007-01-12 14:13]
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hi very good very butiful
Belle image Fréderic, les couleurs sont superbes.
Salutation, François
wow good shot!
A beatiful rainbow and the backround is beatiful too!
I like tha blue.
....Toba