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ArcticMyst Security by Avery

Interesting effect, reportedly from Lyon, France

DrSid

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Take a look at the leftmost beam on my last photo .. there are brightness irregularities. What is interesting is that they are all roughly same length. What if those really drops of oil blurred because of long exposure ? And long exposure it of course is. While the person in front of the fountain is pretty sharp, you can see blur on the clouds. The stars around lightsources also shows that high aperture stop number was used. This could be done just for the look of the street lamps .. but it could also be done to control motion blur .. to increase it. Anyway it would seem to me like way to complicated thing, and the result would be unreliable outside in wind.

And one more picture, even more puzzling. Not sure if it is the same fountain, or same time.

boitemariejeannegauthe_6821.JPG
 
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Very interesting, and very nice to look at but, what if... In the OP picture they were laser beams, and the diffraction grading was spinning? That would look pretty cool.
 
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that last picture almost looks a little photoshoped. well the water in particular.
 
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I agree with big time photoshop on the last picture.

I didn't think about the reflections based on the direction of the beam. If it were a laser and emitted from the top it would reflect off the surface of the water and likely be visible going off to the sides. On the other hand if it were emitted underwater it would be unstable because the surface of the water would directly effect the beam. This leads me to conclude that it would have to be a wire with another means of lighting which may just be oil dripping down a wire that is lit up or it could be fiber optic or a combination of the two.
 
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This is NOT EL wire as it looks like a pulse modulated laser beam either in free space or in a light pipe :thinking



Found one picture:

132026307_31n.jpg


I used google image for: lyon france festival of light 2012
 
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How insanely fast do you think that camera is FP? XD

I would say that the dashed effect on the beam is due entirely to pixelation. The beam is just too thin for the resolution and the compression algorithm wasn't set to fully anti-alias the image.
 
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Why pulse modulated ?

Because the beam is not constant it is turned on and off, see the dashes or gaps in the beam.


@ AP I'm just guessing here but the beam could be modulated at a slow rate but faster than
the human eye could detect so the camera would not have to be like 10,000 frames per
second it could be much slower and still pick up a slowly modulated beam :thinking:
 
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I am pretty sure that something like that isn't possible. The modulation would have to be in beyond fast and the camera would have to be faster than we possess. Otherwise the camera would just see a solid beam just as our eyes would. A modulation just above what our eyes could see would still have to be insane to get that effect if you think about the speed of light and again the camera would still have to be faster than we possess. There is only one setup(in my knowledge) that was made that could catch a laser beam in mid travel but it wasn't a conventional camera.

I have worked with graphics in the past, believe me that is simple pixelation in that image.
 




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