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rainbow over the houses viewed from the old finstown rd
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Picture added on 23 October 2008
Two things are well demonstrated in this nice pic: the 'reversed' spectrum in the outer bow, and the marked difference in brightness and colour saturation between the area within the inner bow and the rest.
Although it's been commented on once or twice, I don't think we've seen a really satisfactory explanation for the latter phenomenon on this site to date. (Please correct me if I'm wrong.)
Added by Ian Hourston on 26 May 2013
I came across an explanation for the light area below a rainbow ,which is:
The light paths for parallel rays through a water droplet which produce the primary rainbow comes from the highest drops which have single reflections. All others reach the eye from lower drops, lightening the sky.
Added by Neil Johnstone on 28 May 2013
I'm afraid that's gobbledegook to me Neil.
Added by Ian Hourston on 30 May 2013
Me too Ian, and it came from a scientific source.What do they say about scientists, something about eggheads.....?
Added by Neil Johnstone on 01 June 2013
In desperation I turned to the fount of all knowledge, Wikipedia, and here is their explanation:
. . . each raindrop is a sphere and it scatters light in a many-layered stack of colored discs over an entire circular disc in the sky, but only the edge of the disc, which is colored, is what is called a rainbow.
Clearly fearing that this hasn't quite got the message across, Wikipedia then quotes an expert:
"Each colour [a momentary lapse into English spelling] has a slightly different-sized disc and since they overlap except for the edge, the overlapping colors give white, which brightens the sky on the inside of the circle. On the edge, however, the different-sized colored discs don't overlap and display their respective colors - a rainbow arc."
Added by Ian Hourston on 05 June 2013
Admirable but I'm afraid still gobbledegook Ian. How say you?
Added by Neil Johnstone on 06 June 2013
I always think of light in terms of stacks of coloured discs, don't you Neil? And when it comes to circular discs (as distinct from, say, square or oblong discs) in the sky, the talk in Stromness is of little else when rainbows are about.
Yes, gobbledegook on stilts.
Added by Ian Hourston on 10 June 2013
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Stone Pillars above Cuween CairnFinstown Telegram and Post OfficeFinstown from WidefordThe Cottage. KirkwallThe Anderson siblings, FinstownPeter Anderson Senior and Family, FinstownKirkwall BasinMain Street, FinstownScapa SunsetA third Stromness football picture