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Old 25-01-2019, 06:32 PM
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Bluknghtv (Daniel)
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polar alignment procedure.

Probably asked before but couldn't find a definitive answer. So when setting up my eq6GT, I align the tripod counter weight leg to due south and then move az dec bolts to find scp finding scp via an app initially and dial in with software? I have read that from due south go 12deg to the east and then find scp. I ask this because when I point due south the scp is way off where I am and the az bolts don't have enough adjustment to reach the S/SE area of the sky.
The only way I can get in the vicinity of roughly where the scp is I need to manually move the tripod more to the SE and virtually in line with the scp? This then doesn't allow the tripod to be pointing due south to start with. Wanting to get out and get this sorted tonight as it's the only clear night I have had really since getting my orion 130 apo. Obviously watching youtube channels most deal with Polaris and up there in the north because polaris is close to due north they don't need to put as much az movement on their mount. I've watched so many vids about it that I'm confused now and it's hard for me where I am as there are no Astro clubs around to go to for help
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Old 25-01-2019, 07:10 PM
Pepper (Steve)
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Point ya mount at 12 deg off south.
Only use the bolts on side if synscan controller prompts you too.
Mount needs to be toward scp not mag south

Last edited by Pepper; 25-01-2019 at 07:11 PM. Reason: Fixing autocorrects.
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Old 25-01-2019, 07:33 PM
Wavytone
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You really need to read this http://www.iceinspace.com.au/forum/s...d.php?t=172879

1. It pays handsomely to level the top of the tripod accurately using a level (smartphone app will do nicely) as this means that once you have the elevation set correctly on the mount it will be very close to right, every time you set up.

2. Use "The Force", Luke.

Let go of the compass, and look up. The stars will guide you. To locate the SCP well enough locate Hadar (Beta Centauri) and Achernar. SCP is close to midway between them. Hold your hand up at arms length to estimate the midpoint.

If you really insist on using a compass, SCP is 12 degrees east of magnetic south. If using a compass, you need to back off 6-10 metres from the mount to prevent the compass being affected by the steel in the mount, ideally stand on the north side of the mount, hold the compass up and sight over the top of the mount.

Last edited by Wavytone; 27-01-2019 at 04:04 PM.
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Old 25-01-2019, 08:15 PM
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Bluknghtv (Daniel)
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cool thanks guys. I thought that was the way to go going 12 deg east. Im using the polar app on the iphone to roughly get scp. From the back yard its a tad hard to find octans but can see the crux. I use the compass app on the phone to find south and I fiddled with the day time scp finder in the iphone app this arvo and pin pointed where the pole was. One thing I also not real sure on is the altitude. It suggests on the app at my location 20m elevation which is too low going off the scp target in the app. 35m is more correct and I believe it's the same if you were in Sydney which is about 3.5 hours away.
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Old 27-01-2019, 11:48 AM
Wavytone
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Not sure if you are aware the elevation of the SCP above the horizon equals your latitude.

If you take care to accurately level the tripod head each time you set up, before setting the mount on top, once adjusted you wont have to fiddle much with this.
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Old 27-01-2019, 12:06 PM
Startrek (Martin)
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To find true south ( celestial south ) I used the solar noon shadow meridian method gets you really close to SCP ready for your PA
I gave away using my Silva compass with magnetic declination as it changes slightly from week to week , month to month due to the variations in magnetic flux commutating around the earth
Now I have a permanent line marked in my 2 locations ( Sydney and South coast ) via the solar noon shadow meridian method and I’m only a degree or less off when I start my PA
Cheers
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Old 27-01-2019, 01:44 PM
Startrek (Martin)
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Daniel

If your from the Burrill lake area ( south coast NSW ) my holiday house is not far from there and I’m down on the weekend for a week
Happy to help you with setting your tripod pointing true south
Pm me with your details if you want

Martin
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Old 09-02-2019, 05:39 PM
SA_Dolphin_22 (Tony)
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Polar Alignment Procedure - Sthn Hemisphere.

Evening, I also had issues with this as there is just far too much info out there. Hopefully three doc's have uploaded for you, two word docs and a video file, If the didn't simply search the net for D.A.R.V. (Digital Alignment by Robert Vice) and then look for youtube videos on drift alignment by Forrest Tanaka, explains it very easy to understand terminology. Cheers

Tony
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Old 09-02-2019, 11:13 PM
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Quote:
Originally Posted by Wavytone View Post

Let go of the compass, and look up. The stars will guide you. To locate the SCP well enough locate Hadar (Beta Centauri) and Achernar. SCP is close to midway between them. Hold your hand up at arms length to estimate the midpoint.
Or extend the long axis (north-south direction: alpha and gamma) of Crux and extend this distance five times southward and you are close (< 1 degree) to the pole.
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Old 11-02-2019, 08:25 AM
Redeye
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there are some apps about, such as "Astro Locator" which will help you get your mount pointing in the right direction. Having said that, the compass apps on most smart phones are a bit iffy. Much better to use a compass and adjust for true south from Magnetic south. The inclimometers (angle finders, spirit levels etcs) in phones are pretty accurate though

Polar alignment is something that I struggled with for quite a while, then happened across a post on IIS, regarding making a baton to rest the compass on, so that you can line the baton up perpendicular to true south. You then place the rear 2 tripod legs against this baton and hey presto!

Post here: http://www.iceinspace.com.au/63-499-0-0-1-0.html

I have sighly modified the approach to make it more flexible, in that the cross piece on the baton I have mounted at right angles to the baton, not at the local magnetic deviation. this enables me to set any deviation on the compass (as I move around a lot) and still use the same baton.

With regards to the altitude adjustment, that is your latitude. The Astro locator app gives you this then if you place the phone flat on the mount saddle and adjust it, it highlights by going bold, when you are at the correct altitude. This takes a lot of guess work out of the setup and gets you close enough to do an accurate polar alignment if needed.

Last edited by Redeye; 11-02-2019 at 12:53 PM.
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Old 15-03-2019, 03:37 PM
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You probably have everything sortted but if you can mount a camera to point the same as your polar axis you can take a time exposure which will show many little star arcs and from them you can get a good idea the direction to adjust.
In fact on my wide field mount that is all I do...and once that was all I did for even longer focal lengths to get very close before a drift alignment.
And the photos of the star circles are rather neat☺.
Alex
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