Re: leveling a tripod

"atasselli@xxxxxxxxxxx" <atasselli@xxxxxxxxxxx> wrote:
Stephen Paul wrote:
Fred Scharmann wrote:
Why is leveling so unimportant to you?

Thinking otherwise is a common misunderstanding...

Quite the opposite...

The polar axis of a mount is an imaginary line that extends from the
azimuth pivot of the mount to the celestial pole. Everything in the sky
rotates around this axis.

The azimuth pivot is the axis the equatorial head rotates about when
adjusting the azimuth. It is NOT the RA axis which is the one that
needs to be aligned to the celestial polar axis.

Erm, yes it is. The RA axis must be parallel to the axis of rotation
of the earth. That is the purpose of, and requirement for, polar
alignment of an equatorial mount, no? In the case of a correctly
aligned equatorial head on a tripod inclined east-west, the azimuth
axis will in fact *not* be pointing along a horizontal projection of
the direction of the celestial pole. But it'll still track the sky
just fine. It might have been tricky to get it aligned, but not
impossible.

If you imagine a correctly aligned eq. mount, rigidly suspended along
its RA axis (and thus remaining in polar alignment), it shouldn't be
too hard to imagine twiddling the altitude and azimuth adjustment
screws over quite some range and still being able to adjust the tripod
legs so they could support the mount.


Tim
--
Did I really still have that sig?
.

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