Re: [ATM] Favorite Spider Designs

[John Lynch <john_lynch2006@yahoo.com>]

Mike,

The best scenario would be an extremely thin
wire-suspended spider, but curved, to take advantage
of both design benefits.  Also, a magnetically
suspended spider would be the ultimate but probably
hard to control.

John Lynch

--- Michael Wheatley <mwheatley@telus.net> wrote:

> I had thought that the spikes around stars,
> diffraction or otherwise, 
> were caused simply by diffraction around the edges
> of the spider so 
> that a wire spider with several times as many edges
> would move more 
> light into the spikes.
> 
> I have since read Texereau's reference to a stable
> layer of air 
> heated or cooled by conduction along the surface of
> spider vanes that 
> throws light into the spikes by refraction.  I
> expect this is why the 
> lack of surface would give the wire spiders an
> advantage.
> 
> Can anyone say off hand what the relative importance
> is of edges 
> (diffraction) and surfaces (refraction)?  Do we also
> have to consider 
> reflection, diffuse and specular, from the vanes?
> 
> I expect the diffraction would be relatively
> predictable while the 
> refraction would depend on temperature differences
> and the reflection 
> would depend on ambient light and surface treatment.
>  I can see why 
> the wire spiders may be best overall.
> 
> Mike Wheatley
> 
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
> 


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 
_______________________________________________
ATM mailing list http://www.atmlist.net/