[ATM] shrouds, baffles, and tubes

[Jay Kirkland <jaykirk2@compusmart.ab.ca>]

Looking at Tele-Vue's solid bronze or brass 1 1/4" to 2" eyepiece 
adapter/counterweight, I noticed that it seems to be left as unblackened 
metal. TeleVue says that its angles have been have instead been designed 
to prevent reflections. There was a good bit of debate last month on the 
list over whether or not to blacken spider components. And I've read on 
various sites a lot of comments about how much certain people hate 
shrouds, etc, and prefer just a couple well placed baffles.
    Now way back when, in Deep Sky Magazine Richard Berry wrote an 
article about optimizing your Newtonian to give it refractor-like 
performance. His fixes included the now standard baffles behind the 
primary and at the bottom of the focuser tube, and velvet or flocking 
opposite the focuser, but also a baffled tube extension about twice the 
apeture in length extending in front of the focuser, as well as a 
baffled tube, and an observing cloth for over your head.
    Over the last 20 years, has all of this been proven to unnecessary? 
Can we do away with shrouds, tubes, etc, and use only a baffle at the 
bottom of the focuser and a baffle opposite the eyepiece and a 
head-shroud and get an image of the same quality? Does this work only 
from very dark sites or can you use an open, unshrouded tube, minimally 
baffled  scope in a light-polluted setting? How important does the 
quality of the baffle material become as light pollution becomes more 
intrusive? Is there a point at which even the most light absorbant 
material, ie velevet, doesn't provide as efffective a solution as an 
old-fashioned fully-baffled scope?
    

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