can beading be bad?

pies said:
To focus the suns light you would need a gap between the lens and the object.Without the gap all that is happening to the rays of light are they are being defracted (spread in different directions) at the water surface as there is no back to the lens the light can not be focused to an exit point.and therefor can not damage your paint.



You are going to get damage caused by the elements contained within each drop.This does not mean every drop of rain is going to damage your paint.Acid rain will given long enough etch your paint but this is a very long process.
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How big of a gap do you need?



You've got a coat of wax on there and the clearcoat, which are both clear and could serve as a space.
 
You need an air gap,sorry if i didn't make it clear,It dosen't matter the the droplet is sitting on wax,clearcote,paint etc.

If you imagime how a camera lens,telescope,binoculars etc works there are air gaps between the elements this allows the light to be focused without the air cap you can not focus the light. :)
 
pies said You need an air gap
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OK - you've lost me (not difficult - Physics was a long time ago) :)



The refraction is caused by the edge of the object, not the media itself. So the droplet would focus the light a set distance from the droplet - and so long as the focus is on the paint it won't matter too much whats in between so long as its perfectly clear.



Back to the plant problem - its real and it happens, but I agree that there the problem is caused by the delicate nature of the plant. I can't see how you could heat the paint to a level that would cause damage without also evaporating the droplet
 
The air gap is required so the other plane (in this case the other side of the droplet) can be curved When the droplet is laying on your paint one side is flat and far too close for accurate focussing to occur

For example get an ordinary magnifing glass hold it about 12" or so from a flat surface,move it around until yo catch a light in the "focus area" you can move the magnifing class back and forward until you get a sharp image.

Now move the magnifing glass right to the flat surface as you do you will se the light gets less focused until you get lhe magnifing glass right onto the surface and the light is almost passing straight through:)



Hope that explains it better im ok in physics my English ain't so good:(
 
When the droplet is laying on your paint one side is flat and far too close for accurate focussing to occur
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But that assumes that the sun is directly above the droplet. I think we are talking about where the sun is hitting the droplet at an angle and hence not passing through the flat part at the bottom :)



Neither my English nor Physics is very good :) but hey what do you expect of a country bumpkin born in Kingston, Nr Canterbury?
 
It dosent matter what angle the sun is at , because the droplet is in direct contact with the surface layer it is not possible to focus the light :)



have you tried the magnifing test :)
 
What about surface tension? Is it possible that the water droplet is not in total contact (in the center) with the paint? That would be your air gap though I still do not believe that the focal length(? focused area) would be sufficient.



I am sticking to the concentrated acid rain concept!:up
 
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