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How do ‘you’ polar align?


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Yep, same as @Skipper Billy I use Polemaster to get close, then drift align.  I do it once every few months as, once you're used to it, it only takes about 40 minutes for a really good alignment, and even if it hasn't changed it means it has been checked.

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I use an iOptron iPolar. It's quick and let's me set up/align before it's even dark enough for me to see Polaris. Anything that gets me ready to go a bit earlier is an advantage.

Sharpcap PA , quick and easy inexpensive, utilise equipment I already have no further purchase required using my guide cam in a qhy miniguide scope .

Visual through the polarscope.  Gets me within 10' almost always and within 5' (which is enough for PHD2) most of the time.

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44 minutes ago, CraigT82 said:

You point the scope (has to be a short FL scope for necessary FoV) at the NCP or close to. Latest sharpcap version will work within 7 degrees of NCP. 

Sharpcap then platesolves the image the scope is seeing, needs about 5 stars minimum to do the solve.

The you rotate the mount in RA about 90 degrees and platesolve another image there.

Sharpcap then knows where the mount is aligned to, relative to the NCP, and then highlights a random star on screen and gives you an arrow and a target on the screen. You need to move the highlighted star along the arrow to the target using the altaz adjusters. 

Thanks for the clarification Craig, I wasn't sure of how it worked.

That confirms Polemaster for me then,  although it's quite expensive compared to just using Sharpcap's software functionality with the main scope, the convenience of the Polemaster camera being permanently aligned to the scope's RA axis is a big enough timesaver for me, being able to use it any time by just firing up the software, regardless of where the scope is pointing, (even in mid session).

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4 minutes ago, Annehouw said:

I now use this same Polemaster on my iEQ30Pro. I use it with a laptop, but there is an Android version of the SW as well.

Interesting Anne. I have some Android devices and have just installed the software onto them. I will try them out using Android as I normally use a Windows laptop to polar align despite imaging with a Raspberry PI. Thanks for the heads up.

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I use the polar alignment routine in Ekos (I run INDI/Ekos) which is a plate solving method like Sharpcap (never used sharpcap so I cannot compare).

I cannot stand to have to look through a polar scope on a wet terrain :) my old knees would not take it anyway ... 

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Sharpcap. I used to have a Polemaster and both give near similar results. If anything, I think Sharpcap is a bit more accurate and you only have to rotate the mount once where Polemaster is more fiddly, more steps involved and more user input needed. Also, grossly overpriced given the availability of Sharpcap for £10.

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20 minutes ago, Astro-Geek said:

Thanks for the clarification Craig, I wasn't sure of how it worked.

That confirms Polemaster for me then,  although it's quite expensive compared to just using Sharpcap's software functionality with the main scope, the convenience of the Polemaster camera being permanently aligned to the scope's RA axis is a big enough timesaver for me, being able to use it any time by just firing up the software, regardless of where the scope is pointing, (even in mid session).

Polemaster is very good particularly because of the convenience, as you rightly say.  Software wise both Polemaster and Sharpcap do the same, very good, job but if like me you use an OAG, or do not use guiding so don't have access to the specified FOV then Sharpcap could be out of the question.  Polemaster is also easy to swap to other imaging rigs as well if you run a couple at a time, such as one for DSO's and a smaller one for wide field.

All options are very good and perfectly capable of obtaining a very good level of PA, but Polemaster also provides the necessary hardware, which is why it is more expensive naturally.

Edited by RayD
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18 minutes ago, Astro-Geek said:

the convenience of the Polemaster camera being permanently aligned to the scope's RA axis is a big enough timesaver for me, being able to use it any time by just firing up the software, regardless of where the scope is pointing, (even in mid session).

That's a very good point.

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1 hour ago, JamesF said:

If I have a view of the NCP then I use the PA system in Ekos.  If not then I drift align using PHD2.

James

I tried that last night after my imaging session last night and I was so far off the purple line ended up way to the right off the screen. Any Ideas on which way to move the mount ?

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2 minutes ago, MarkAR said:

I tried that last night after my imaging session last night and I was so far off the purple line ended up way to the right off the screen. Any Ideas on which way to move the mount ?

Which one are we talking about here?  Ekos, or PHD2?

James

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I use an iOptron iPolar. It's quick and let's me set up/align before it's even dark enough for me to see Polaris. Anything that gets me ready to go a bit earlier is an advantage.

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14 minutes ago, MarkAR said:

Ekos.

If I recall correctly (and it's a few months since I last used it so I may be mistaken), one end of the purple line should have a green circle on it.  That's where the RA axis is pointing now.  You need to move a star from the other end of the purple line to the end that has the green circle.  You can move the line to put a bright star at the other end.  I can't recall if the green circle moves with it, but obviously it's pretty easy to remember which was which.

If you can't see the green circle end of the line because it's off the screen then I'd just move a star from the other end of the line some distance along it and repeat the process until you can see both ends.  Equally if you can only see the end with the green circle, just move a star from somewhere in the general direction of the other end of the line to the green circle and repeat the process.

I'm fairly sure that's what I did.  As long as you can see one end, can identify which it is and move a star roughly in the right direction to get nearer the green circle end then you should get to the point where you can see both ends after a few passes as your alignment becomes closer.

James

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You can see a demontration here from the main developper, Jasem

 

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Hmmm... A "posh" digital level plus a "shadow" at local solar noon. (Part serious!)
But then I change scopes such a lot... I suspect "cone errors" etc. etc. of the many
different setups (scope, dovetail, tube rings etc.) preclude "delusions of accuracy"? 🥳

I initially find stuff (remotely via video finder / screen!) *then* EQMOd finds / tracks
well enough for EEVA. But I must get in there and cure the HEQ5 "backlash" thing. 🙄
(OK, a permanent observatory setup, is a bit easier than a constantly shifting one?!?)

Edited by Macavity
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For the portable rig Sharpcap and a finder and old cam I rigged up for the purpose.

For the home pier/mount Sharpcap then drift aligned a good while ago, maybe 2 years.

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When Bernie(Modern Astronomy) sold me my first imaging scope(Skywatcher 120p andEq6R Pro) he included the Polemaster and so have never knelt down and prayed for Polar Alignment🙏🧎

Roger

Edited by apophisOAS
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So far I've been using the polar scope in my HEQ5 Pro along with the Synscanini2 app.  Have a 90º angle finder for the polar scope, with built-in magnification which makes it a lot less ackward, and more precise.

However, am using an autonomous autoguider which has a polar alignment routine too. Have tried it unsuccessfully a couple of times, but know I did it wrongly the first time, and possibly also the 2nd time.  If I can get it to work, it seems a nicer and much more comfortable way than using the polar scope, as it uses the display on my phone.

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  • 2 weeks later...

If I point my mount at Bill's chimney next door that's normally in the ball park 🤣

I do use a polar finder app and align visually. +1 for Sharpcap Pro and it's alignment routine. I seem to get acceptable results from visual though (for now).

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  • 2 weeks later...
1 hour ago, Bobby1970 said:

Is this with ASIAIR ??

 

Cant wait to get mine. 🙂

Yes.  And im not sure if its the most accurate.  But it guides also.  So why spend 300+€ on a polemaster when the complete asiair does it also.   I did notice when manual polaraligned, and really spend time on doing a accurate job, the asiair let me do some adjustments afterwards.  And after that second method with the asiair, the polaralignment in the synscan menu asked again for adjustment!

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+ another 1 for polemaster. I bought mine in a fit of pique and frustration at 1am after a particularly difficult imaging session where I'd messed up the polar alignment again, after forgetting the procedure. The following morning I had massive buyers' remorse. 300 quid for a webcam and a fancy lead?  Come on!....But after it turned up and I tried it I have never looked back. It's convenient to use and setup can be finished in 2 mins. I've never had to refocus it since I bought it. It gives all the accuracy I can use,  and PHD2 turns in sub arcsecond results any night when the sky is even halfway decent. My main source of tracking error is now me walking on the slightly uneven flagstones on which the mount tripod sits.

The software does one job only and it "just works" which is rare in my experience. The only time it goes wrong is if I'm running 3 cameras on the same USB port..which is my mistake because it can be disconnected once PA is set up. 

And as has already been pointed out, it can be left running as a constant check, and is easily transferred to other mounts. 

If I had a fixed mount in an observatory it would be less useful, but if you have to set up from scratch every time then the consistency of results makes it money well spent IMHO, even if I could have bought a Delos for the same cash. 

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