Re: [ATM] Baffles

[johncdeitz@comcast.net]

Baffles are placed to prevent reflections from the sides of the tube entering the light path. If the tube nearest the mirror end is of a greater dimension then light from the front of the tube cannot fall against the side. Hence, with a greater diameter tube at the rear no baffles need be cut in this region. And yes, tube weight goes up, but some of the weight is saved in that 1)baffles are not needed, 2) less need for insulation. Also, air currents against the tube are no longer in the light path.
John
 -------------- Original message ----------------------
From: Anthony Stillman <atmer@flash.net>
> 
> 
> >...baffle a
> > six inch scope- use 10+in diam 
> > tube at the mirror end and "nest" the 8in diameter
> > tube in it at the open end.
> > Astronomy Magazine
> 
> 
> How is it that making the mirror end of the tube
> larger in diameter will reduce the number of baffles? 
> I don't get it, or Astronomy Magazine either.  It
> seems to me all this does is replace a light weight
> baffle with more heavy tubing.
> 
> Anthony
> 
> obiter dittum
> No legal bearing.


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