Re: [ATM] Advice on Solar scopes/observation

["Tom and Beth" <milliesand@cox.net>]

A few comments on Solar Scopes:

Baader film is perhaps the cheapest material to make a filter with, and even 
with a 3 inch scope will show granularity on the sun (as long as your local 
seeing permits). Yet, I've seen comments about (effectively) making the 
filter holder so large it becomes a sail. Should the filter blow off, the 
damage to your eye is instantaneous, permanent, and significant. Therefore, 
a few nylon screws, preferably into the top end of the scope, is a wise 
choice.

Since your scope is pointed directly at the Sun, the tube color makes 
little, if any, difference. And the best time for Solar Observations is 
early in the morning.

The purpose of the Light Shield is to facilitate looking in the eyepiece and 
seeing detail. A cheap straw hat in your hand works just as well. Putting a 
big "sail" on the telescope will make the scope shake. You wouldn't want you 
scope shaking at night, why permit it during the day?

In January of 2004 (IIRC) Sky and Telescope had an article by Harold Suiter 
on increasing contrast in scopes. One of his pictures was of a Solar scope 
that utilized an uncoated mirror and a Hershel Wedge as the secondary. In 
that particular scope, most of the internal surfaces were white to minimize 
heat currents.I have looked around for this wedge to no avail. I CAN find a 
Hershel wedge for REFRACTORs though.

Disclaimer: I use Baader film on my solar scope every day. ;-)

Tom 


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