Re: ATM 3-Vane or 4-Vane Spiders

[Myosin@aol.com]

this is the type that Wm Herschel used, hence called the Herschellian. Need v 
long fl

Frank


In a message dated 10/5/01 2:04:08 PM, stjeanp@pat-st-jean.com writes:

<< What about the, for lack of a better word, non-Newtonian reflectors I've
seen pictures of?  The ones where the primary is angled so that the main
tube is clear of obstructions...  Is there anything special that needs
to be done when making a mirror for them? >>