For an object at the celestial equator, I don¡¯t think cone error will have any first-order impact on guiding. It shouldn¡¯t lead to the drift in declination that Magnus is seeing. This also means that drift alignment should not be affected by cone error.
-Les
On 20 Nov 2017, at 12:34, David Pickett yahoo@... [Losmandy_users] <Losmandy_users@...> wrote:
At 21:17 20-11-17,
jfev5mnsvqiyzpq756wvokt55jve7sbg2esr5mip@... [Losmandy_us wrote:
Isn't cone error something else? That does not
"affect" polar alignment, but causes field
rotation and similar problems. I mean, polar
alignment and drift alignment depends on the
mount, not on how the scope is mounted on the mount. Or am I wrong?
Cone error is when the axis of the OTA is not
parallel to the RA axis. Then, even though the
mount is accurately polar aligned, the OTA
describes a cone around the projection of the
polar axis. Easy to visualise by imagining that a
refractor is at a 45¡ã angle to the RA axis. Then
as the axis turns the OTA will also turn and will
always be pointing somewhere else other than the NCP.
I am not sure that this explains your problem however.
But what on earth could that be? I mean, flex in
the guidescope could not possible cause this, right?
If the guidescope is leaning one way before the
flip and its mounting is loose enough to make it
lean the other way afterwards, I should have
thought it quite possible that this is the reason
for your problem. At all events, I think that
_something_ is moving as the flip happens.
David
------------------------------------
Posted by: David Pickett <yahoo@...>
------------------------------------
------------------------------------
Yahoo Groups Links
[Non-text portions of this message have been removed]
