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[Paul Haese]

12 minutes with the star sitting on the line in the reticle.  I could do a lot better, but John is more reknown for that than I am.

[Exfso]

No movement up or down from the line. You dont use the centre of the crosshairs to do the alignment. Align the cross hairs so that the up/down buttons on your controller run the star along one of the lines.  Next move the star to the other cross line and place it in the centre of one of the left/right lines, just out a bit from the centre. The idea is to keep the star from moving above or below that line. (Up/down=Dec. Left/right=RA buttons on your hand controller) I hope this makes sense Stu..

[Paul Haese]

The horizontal stadia Stu is for left and right movement of the star. So just rotate the reticle until the star you are using moves exactly along the line of the horizontal stadia. Then do what Pete said.

[stu]

Align the cross hairs so that the up/down buttons on your controller run the star along one of the lines.
...
 (Up/down=Dec. Left/right=RA buttons on your hand controller) I hope this makes sense Stu..

I've been using L/R buttons (RA) alignment for both the meridian and eastern

[westsky]

Just thought I would post this so as to confuse people even more 

Drift Alignment in detail
The explanation of how to polar align using the drift method is as follows. In this procedure, adjusting the RA isn't important, just leave it, drift in the RA is just a case of your motor being slow/fast, not an alignment problem.

   1. Point the telescope to a bright star low-ish (20 degrees say) on the eastern horizon, near the celestial equator (the line of 0 degrees DEC, something like the Orion nebula is fairly close, and good to look at in the mean time (given the right time of the year - it may be too high/not visible.) At this point the east/west rotation of the mount has minimal effect, leaving you to correct the angle of elevation of the mount.
         1. If the star drifts NORTH your polar axis is too low. So you have to change the axis to angle up into the sky more. (the latitude knob on your eq mount.)
         2. If the star drifts SOUTH your polar axis is too high. So you have to change the axis to angle down into the ground more. (the latitude knob on your eq mount.)

      What do I mean by "drifts NORTH" and "drifts SOUTH" ? In the field of view or what??. Well this is what got me stuck for ages. The way I do it now, is you let the star drift for a bit, you then move the telescope to 'catch up with it' by using the DEC control. If you find the telescope is heading north, then the star is drifting north! :-) and that's what they mean by "drifts North".
   2. Point the telescope to a bright star on the Meridian and on the celestial equator. So this is basically straight over your head somewhere. This way the angle of elevation of the mount (corrected above hopefully) will have minimal effect, leaving you to just correct the east/west rotation of the mount.
         1. If the star drifts NORTH your polar axis is too far East, so rotate the mount west. (Rotate clockwise looking down on the mount).
         2. If the star drifts SOUTH your polar axis is too far West, so rotate the mount east. (Rotate anti-clockwise looking down on the mount).

      Again, What do I mean by "drifts NORTH" and "drifts SOUTH"? Well even though we are testing the rotation not the angle of elevation, it's the same as I described above basically.

cheers
David.

[stu]

Thanks west sky.
As I found out last night, there is a trick to doing this that know one ever tells you. When you adjust the mount, the star moves 1% in the direction you want it to and 99% at right angle to that plane! This confused me for ages, I thought I was adjusting the wrong knobs. Took me till 3:30am this morning to figure that out. Tonight it only took me 1/2hr to align, yesterday it was 5 and a half hours and I went nowhere.

[Paul Haese]

Yeah I reckon everyone goes through this Stu. It is hard to describe what you see happening with the star. Glad you got it.

[westsky]

Your'e welcome Stu anything to make it easier, by the way these are not my instructions I got them of the web somewhere, can't remember where though.

It used to take me a couple of hours to get a good drift but now using these instructions it only takes about 10 mins, you will get the hang of it just takes more practise.

David.

[Danny Boy]

The steps I use, which makes it easier for me to remember (in essence repeating what has been said above)???

-Using a compass, point mount at 172 degrees (Adelaide).
-Usually for altitude I leave the mount to where it was the previous session ? usually only requires minor adjustment when doing the drift alignment.
-Pick a star on the meridian just north of the celestial equator. For this step I usually pick a star just east of the meridian such that I am facing north and the OTA is on the left of the mount and the counterweights on the right.  I find this helps that when I go to choose a star on the eastern horizon, I only move the mount in RA.
-Orient the reticule such that the star moves N-S and E-W along the reticule lines.
-If the star moves up, I adjust (tighten) the right knob on the azimuth of the mount.
-If the star moves down, I adjust (tighten) the left knob on the azimuth of the mount.
-Once I am happy that no drift is seen for at least 5 minutes I ensure the knobs are locked and I point the scope to the eastern horizon. As most times I am doing this in the backyard, I try and find a star just above the neighbours roof line.
-I then rotate the diagonal such that I am looking through the scope standing facing the direction I am looking at.
-I reorientate the reticule such that the star follows the N-S and E-W buttons.
-For this step I hold the hand controller at 90 degrees in my hand to match the movement of the N-S buttons.
-If the stars moves North (that is to the left as I am looking into the eyepiece) I adjust (tighten) the right altitude knob on the mount.
-If the stars moves South (that is to the right as I am looking into the eyepiece) I adjust (tighten) the left altitude knob on the mount.
-Once I am satisfied, I lock the knobs and redo the goto alignment.

This may sound more complicated but I find it works for me.

This is for a HEQ5 mount with a SCT (with diagonal).

Attached is an example of a 3 minute exposure I did at Arkaroola unguided (excuse the poor focus).

[attachment deleted by admin]

[attachment deleted by admin]

[westsky]

Just got this link from a friend , this is what he had to say.
I have been using freeware called Polar Align Max last couple of nights to better align the lx200 on the pole.
It started at 18 arc min away from the pole, and after 4 iterations, it is now 3arc min. I tested its pointing accuracy and found I could slew from Alnair in the west to Betelgeuse, 113 degrees east, and from Archenar to Hamal, 90 degrees north, and still maintain the target close to the centre of the ST8 chip....amazing, I've never had such accuracy before.

I have downloaded it and will try it out this weekend, you do need to have CCDsoft or MaximDL to use it.
It is freeware.

http://users.bsdwebsolutions.com/%7Elarryweber/PoleAlignMaxDownload.htm

there is also Pempro,
http://www.ccdware.com/products/pempro/
As yet I havent used this either, it is only a trial version but good for 60 days.

Cheers
David.

 

[Paul Haese]

It sounds like a great program David. Thanks for the links.

[Asimov]

Being in the NH, I have to do it somewhat differently obviously. It took awhile to get the gist of it but now its very easy!

For the record I used this. TY to the guy who wrote it.

http://www.darkskyimages.com/gpolar.html

[AlexN]

I must give the greatest of thanks to Exfso for posting this document.

I drift aligned only 3 times so far, all 3 times were successful using this guide, and im getting better each time... Tonight it took me just under 1 hour, and I drift aligned with the C11 @ F/30

I got 5mins with no (or not visible) drift at the meridian or in the east using a 12mm reticule @ 8400mm... I dare say she's spot on

Thanks again be to Exfso!

Champion! 

[Paul Haese]

Actually your statement here Darryl in regard to what happens when you place the star in the east west alignment in the reticle is completely wrong. You rotate the reticle until the star when moved in the east west buttons travels along it. It does not matter whether the mount is near polar alignment or not, you rotate the reticle and the diag to suit. You don't have to leave it in any particular position. Then you place the star on one of the lines near the centre and watch to see which way the star travels. For the meridian star, if it travels south or to the right then move in that direction. Or if it moves north or to the left then move the star in that direction.