Polar Alignment in the Southern Hemisphere from a Light Polluted Location.

Flint
29 Feb, 2016 03:53
I am looking for a little assistance when it comes to achieving an accurate polar alignment of my Sky Watcher Star Adventurer mount.

From my backyard I have one location only where I have an unrestricted view of polar sth. The difficulty for me lies in the fact that the southern direction (all directions really) is quite light polluted (red zone). This makes it very hard to see the stars in Octans that I should be lining up with my polar scope.

My current method is to align to 179deg south and adjust the mount to the correct azimuth. From there I have been using the drift align function in Backyard EOS.
And here is where I am getting a little lost. I have read articles on drift aligning, but all these have been northern hemisphere centric. I am having difficulties working out what direction I need to tweak the mount as it relates to the observed error in drift, in the southern hemisphere.

If anyone can point me to a good resource that can help explain it to me, or if someone out there can give me some tips on this, I would be very appreciative.

I can get very close but not anywhere near close enough to pull of a 2 minute sub @ 420mm.
About the best I have achieved is 30 seconds, and even then the stars a trailing a little…
KuriousGeorge
29 Feb, 2016 21:06
Usually trial and error for that. Just take notes on which direction you needed to turn the screw(s) to minimize the slope.

I like PHD2's drift alignment. Also see if your mount has PEC.
Edited 29 Feb, 2016 21:06
toxophilus
03 Jun, 2016 12:37
I bought a QHY Polemaster which, with the latest version supports both hemispheres. It's got a really sensitive camera and I have been getting or close to 30 arc second alignments within 4-5 minutes of setting up. It also allows me to PA before it gets dark. If you want even more accuracy you then it gives you a bit more time to drift align as well, which should be easier as you know that you will be very close to right, however unless you are doing really long subs its probably unnecessary. I know its quite pricey but for the time saving its given me and the ease of set-up it has been worth every penny.
Edited 03 Jun, 2016 13:41
planethunter
03 Jun, 2016 13:11
I did a lot of experimentation with the drift method for polar alignment.  I was able to get unguided subs around 2-3 min on a regular basis.  One of the best explanations I found was here Drift.  I found that to get the best results I needed to use an illuminated reticle eyepiece.  And the magnification needed to be around 250x when performing the drift alignment.
Stefannebula
10 Jun, 2016 09:23
I have to agree with toxophilus, I also live in light polluted southern hemisphere and bought a QHYCCD Polemaster. As painful as it is forking out the $$$ It's by far one of the best thing's i've bought for my setup. Otherwise PHD2 Drift Aligning would be the next easiest option
Edited 10 Jun, 2016 09:24
craig_rodgers
10 Jun, 2016 12:26
Call me lazy, but drift alignment drove me mad, I also opted for a polemaster, 5min alignment vs 30mins or more…Looks like there is at least one polemaster adapter for the Star Adventurer too.

http://www.modernastronomy.com/shop/accessories/adapters/polemaster-adapter-for-star-adventurer/
Flint
11 Jun, 2016 04:18
Thanks very much for the replies and advice.

The polemaster certainly looks like the solution to my woes.
Now to add it into my upgrade presentation to SWMBO smile
samuelpkco
22 Sep, 2016 17:35
Flint wrote:
"And here is where I am getting a little lost. I have read articles on drift aligning, but all these have been northern hemisphere centric. I am having difficulties working out what direction I need to tweak the mount as it relates to the observed error in drift, in the southern hemisphere.

If anyone can point me to a good resource that can help explain it to me, or if someone out there can give me some tips on this, I would be very appreciative."

Just see this thread today and sorry about responding to a few month old post.
I am in the Southern Hemisphere too, with SCP blocked  from sight. So drift is the only way to polar align.
Same set of rules applicable to BOTH hemispheres as follow:-

1) Eastern horizon star drifts TOWARDS THE POLE = mount altitude TOO HIGH.
2) Meridian star drifts TOWARDS THE POLE = mount azimuth TOO WEST.
( ease of remembering - PHW  pole high west ) smile

clear skies,
Samuel
Slawomir
23 Sep, 2016 03:38
I think you might be asking too much of Star Adventurer; unguided imaging at 420mm would certainly lead to star elongation even with 30 second subs with this mount. I think this mount will track well enough within 50-80mm range for 1 to 2 min subs max when properly polar aligned. Here is a bit of info on that: http://philhart.com/content/star-adventurer-review
 
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