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this is macquaire samaarambhaam gorg

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I've been asked why clouds and wires

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some things sometimes appear to be

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behind the Sun well the reason is

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because the Sun is so bright it

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basically washes out anything that's

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imprinted it that is partially

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transparent or is small enough or is

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out-of-focus enough that the sun's light

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basically goes through it or around it I

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can demonstrate that with this little

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setup I have here is a work light behind

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a board with some white paper simulating

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the Sun and I've got some old film

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strips and a small antenna to simulate

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clouds and cables so I'm going to go

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ahead and switch the Sun on and you'll

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see straight away that the film strip in

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the middle which is simulating a cloud

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has disappeared where the Sun it looks

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like it's going behind the Sun and the

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wire itself also similarly seems to be

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going behind the Sun now I'm going to

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zoom in a bit to see what's a more

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typical video of the Sun with things

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going behind it and you see here there's

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the Sun and the film strips are going

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behind it now if I adjust the focus so

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things are in focus you'll see the the

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antenna which is a solid object pops

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into visibility because it is actually

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blocking the light from the Sun however

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you only see it if it's in focus if you

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go slightly out of focus it disappears

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come back into focus and there it is

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again now doesn't matter how much I

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focus the filmstrip never pops into

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visibility that's because the filmstrip

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is transparent so no matter how much you

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focus it is the sun's light is always

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going through it now I've got some other

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film strips on the side and I'm going to

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move those over the film strip in the

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middle and as I move

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whereas a time this is the same thing as

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making a cloud more and more dense

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you'll see that the film strip which is

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simulating a cloud is becoming more and

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more visible and when we've got four

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strips on you can see that the cloud /

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film strip now appears to be going in

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front of the Sun and you'll see that the

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edges of it are still washed out because

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there are more transparent than the rest

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of it but the solid dark parts of it are

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picked up going in front of the Sun so

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there you have it the reason why things

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appear to be going in front of the Sun

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is that the Sun is so bright and if

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something is transparent like a cloud

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and the Sun is behind it then it will

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look like it is going behind the Sun

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when in fact in front of the Sun and

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with the small objects it's more to do

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with them being in focus if the object