Re: (ATM) atm German mounting - one more try
Mel Bartels (mbartels@efn.org)
Thu, 10 Aug 1995 08:52:45 -0700 (PDT)
Boy, I would not be happy with any measurable deviation on my main polar
shaft at all. Deviation also implies vibration. Vibration about the
polar axis is very bad because it will be of exasperatingly low
frequency. A good test of scope overall deviation is to hang a 2 lb
weight (weight choosen because it = CCD cameras, heavy eyepieces) and,
using a reticle eyepiece at very high X, measure deflection. I offer my
20" dob, which deflects 2 arcseconds when hanging 2 lbs at the focuser.