Hi Peter,
Just a couple of suggestions for you.
Firstly just to be absolutely certain that you are picking true south, you
might want to do a quick Alt setup which you say is ok. Then when you are
happy with that, goto sigma Oct. It is star #351. When you have it you now
know exactly where true south is both in elevation and Azimuth. As for
Azimuth, mark a point (maybe on your fences, buildings) so that you have a
permanent line running N/S. Refit your wedge, make sure you have the polar
angle set to your latitude. Note that you already have a good idea from
your altaz setup what the angle should be. No insult intended but it might
be possible to have set your wedge to the compliment of your latitude angle.
What I mean is as latitudes approach 45deg the difference between 40 and 50
is not as obvious as say between 30 and 60( just a thought).
I'm not sure what your latitude is down there in Vic, up here around Sydney
it is 34 deg, that is why I guess you are getting up around Lat 40++.
In my set up I can't even see Sigma Oct. thanks to a wonderful. neighbour
that thinks everyone should live in pine forest. I just press enter as soon
as my 12"LX200 thinks it has found Sigma; why disillusion it? And then
centre the next star it selects. I have found though that if I want really
good goto I have to turn on the High precision feature.
Not bragging but in case you are wondering, I can track unguided for several
hours in Polar so don't confuse accurate goto with accurate polar alignment.

The other thing to make sure of is that you set the N/S switch to the south
position. I think you say that you do, but I'm not sure. That switch has
no effect in Altaz mode that I could ever find, but it a must for polar, but
I guess you would know if that was the problem.

Good luck and keep us posted,

Doug

----- Original Message -----
Sent: Friday, November 07, 2003 2:28 PM
Subject: [M]: Southern Polar Alignment


> Hi group,
>
> I don't know why, but polar alignment has me stumped! I'll try and explain
> what happens:
>
> 12" LX200 on Meade (unmodified) Superwedge. I am in the Southern
Hemisphere.
>
> Okay, scope placed in 'Pole Home' position and tripod level. Checked and
> found stars rotating around centre of EP. Autostar in Polar mode and then
> tried easy and 1 star alignment, both times went to Sigma Octantis - was a
> bit difficult 'cause of the Moon brightness, adjusted wedge to align that
> star. Then Autostar chose Canopus, I aligned with keypad arrows.
>
> I went on to try drift alignemnt for the first time, but, and this has
> happened a couple of times previously to me at this point, when I did a
> goto, the object was well and truly off the mark. Anywhere from about 1 -
5
> degrees out and to the left of the object (when looking straight up at the
> sky). Even a goto canopus was out like this. So something is obviously
> wrong with my setup at this point. I tried this Polar alignment about
three
> times last night and each time my goto's were way out.
>
> Nevertheless, I still tried a drift alignment. Chose a star (with the help
> of Astroplanner) to the North, near the Meridian etc. The star drfited
down
> in the EP, so I adjusted the horizontal axis of the wedge. But no matter
> which way I went (and I mean I went to the extremes both ways), I could
not
> make any differnce at all to the star drift. It did not improve or change
> at all.
>
> I have read as much as I can find on the web. But find that confusing. For
> example the Meade manual says leave the motors running when polar
aligning,
> but I read elsewhere to leave motors off. I have often found conflicting
> advice. (I kept the motors running last night).
>
> I know this is not really that hard, but like I said, I am extremely
> frustrated and lost as to what I am doing wrong. In normal alt/alz my
> goto's are pretty okay and have always been. I have the 1.7k version of
> Autostar. What I find particularly weird is my goto's in polar mode are
way
> off. Perhaps I am not picking Sigma Octantis properly...it is a hard star
> to pick...we are not so lucky to have a Polaris down south here! But I
have
> studied star charts to get an idea of the area and I have slewed in
alt/alz
> mode a few times to Sig Oct to get to know it. Even if I picked a wrong
> star close by, surely my goto's wouldn't be that far out?? Or would they??
> Once again, I am sure my initial setup in Polar home is correct. And yes,
I
> allow for pointing true south etc.
>
> Any help would be very muchly appreciated!!!!!!! I hace a good CCD that i
> have been practising with in alt/alz. But of course I need to be polar
> aligned to get longer integrations and this is really driving me nuts!!
>
>
> TIA,
>
>
>
>
>
> peter
> birregurra...australia
>
>

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