A couple of degrees is prety substantial and I'm not sure if the load is
causing it or not. However, for the longevity of the drives, given their
less than impressive robustness, I highly recommend you balance the scope,
both in RA and in declination. Declination's the easy part, simply balance
the OTA and accessories for complete balance up and down, regardless of
scope orientation. This will require a two dimensional set of
counterweights, such as the Losmandy set. In RA, the scope is somewhat
imbalanced towards the west. You'll want to place weight, most likely on
the left fork, to maintain this same degree of imbalance. It requires a bit
of fiddling but it's worth the effort. That's for a polar mounted scope,
for an Alt-Az configuration, just make sure the scope is balanced in
altitude.

Mike

-----Original Message-----
From: Michael Payne
To: MAPUG
Sent: 10/25/98 8:29 AM
Subject: [M]: Balance & Alignment

Hello,

I hope the readers of this list have some insight into this.

I recently added a NGF-S focuser to my 8 " LX-200. I also use a
Celestron 2" Star Diagonal and I frequently use heavy Nagler or PLossl
eyepieces.

Since adding the focuser I find that no matter how accurately I alt-az
align the scope, (using a known site, accurate time, and two star
alignment) the scope is off substantially--a couple of degrees--when it
then goes to an object in the database.

For example the other night I aligned on Fomalhaut andCapella (in that
order) and then when I instructed the scope to go to M-2 the scope
inaccurately tracked, i.e. M-2 was out of the aligning eyepiece's FOV.

My question: is the scope now enough out of balance that it is affecting
the accuracy of slewing to database objects? The DEC motor doesn't seem
to be working too hard so I hadn't thought it necessary to get
counterweights; but if the slewing accuracy is now affected by the
weight, maybe I should.

Suggestions? Thanks in advance.

Michael Payne

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