Re: [ATM] Advice on Solar scopes/observation

[Mike Lockwood <melockwo@uiuc.edu>]

Hi,

Last week, I wrote:
> A closed, insulated tube is good.
> That's why the Daley scope is neat - it has a tilted window that only 
> lets through a small amount of the light in.  That reduces the intensity 
> of light entering the tube, so there isn't nearly as much to scatter.  
> This reduces the requirements down to something more like a normal scope.
> The tilted window allows folding with no central obstruction, for a 
> compact unobstructed scope.
> The optical demands are not that tough due to daytime seeing usually 
> being fairly bad.

With the mention of the Baader solar film, that reminded me of the 
last Venus transit.  For that event I made a filter for my 25x100 
Oberwerk binoculars from the Baader film, and this worked wonderfully 
for viewing the transit.

An unexpected benefit was that after the transit, once the sun got up 
a bit higher, the low-contrast detail on the sun through the binos was 
outstanding.  Not quite as good as the Daley scope, but the binos gave 
lower power than the long-focus Daley, and larger features stood out 
better.  The Baader film is good stuff, way better than Mylar or glass 
filters, and less expensive than the latter.

	Mike Lockwood

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