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Precise Polar alignment/3 star/plate solve...help


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Ok, as I mentioned in the welcome forum, I'm not new to photography, neither actually to astronomy (observe stars/planets), and I'm fine working with some finicky software also, I work in the IT field (when they want me to). 
What I'm new to is, putting it all together and understand how it all works together. 
So it's best to say what I did last night and the problems I ran into.  
 

So EQ-6R Pro mount has a USB connection (USB A to B  and I'm running it with a long extension usb cord (it has a built in signal repeater ) 
DSLR Camera choice , is something I kinda regret buying right now  (Pentax) since it doesn't have remote live-view via USB like Canon or Nikon, so that really sucks, I really want to see test shots in my nice warm garage, and without freezing to death next to it on a 2 inch lcd screen. 

The guide cam is not great, although sharpcap recognizes it, it's very poor, it's one of those no-brand things that sold with cheap kits, although it sees stars with a lot of gain/brightness applied.

I'll get another one later. 

 

Anyway, the problem. 
In SharpCap (which I paid 1 year license fee)  has a really cool precise polar alignment option, which relies on plate solving sorta,  and supposedly really nails the mount to a very high precision alignment or it's claims so. 

Question: 
Do I still need to go through the 3 star alignment?  I thought a well polar aligned mount doesn't need other stuff, unless some internal mapping software needs coordinates, correct? 
My problem is, that I can't get 3 stars, even 2 stars can get challenging at my location. I know, crazy, but I have a limited open sky, due to trees and buildings, but I know what I want to observe and photograph in my limited view, just be there at the right place/time. 

I know, sucks, but I got a clear view to most of the things toward the  South/East and South sky above my house  my issue is East/West and  Northwest. 

And somehow using the Skywatcher  alignment software exclusively seem to be picking stars that are behind a building or a tree. (I'm talking about the software that comes with the hand controller). 

So the 3 star thing can take me a while, especially if I'm thrown some star names that I don't exactly recognize and being a "shiny star" doesn't work in my DSLR LCD or guide scope, because suddenly half all the stars are shiny and I'm afraid I'm locking onto the wrong star. 

So I end up slewing all over the place and wasting my time with it. 

And I really hate switching to an eye piece in 22 degree weather, and then I need couplers and whatnot due to the focal length is now incorrect , and I neither have a laser pointer or a TelRad and I thought I could get away with a 50mm guide scope with a guide camera. 
Question: 
-Can I just do plate solving and forget about the 2 star or 3 star alignment? Isn't that just for casual observing? The Skywatcher software is not counting on that I am already polar aligned? 
Isn't a precise polar alignment is enough, so I could just navigate to my target and start doing what I want ? 

If not, what's my next step after the mount is polar aligned and I set the EQMOD as it's "parked" there? 

Are there any steps I still need to take?  Should I just download some plate solving software and start fiddling with that too? 

Thanks! 

Edited by Unimatrix0
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Polar alignment and star alignment are different things.

Polar alignment sets the mounts RA axis to point at the celestial pole so that it tracks accurately. This is essential although some people go overboard. As a general rule, accuracy to within about 5 arc minutes is sufficient.

Star alignment adjusts the coordinate system so that gotos are accurate. This is not really necessary when imaging as you can use plate solving to get precisely on target. It can be handy for observing so you don't need to go hunting around for your target.

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I would recommend  installing Astrophotographytool  ,https://www.astrophotography.app/  though not sure on using the Pentax with APT , I think there is a work around but you would need to check with Ivo @Yoddhaon APT forum , (I’d probably look for a cheap canon body tbh less hassle )then you could connect camera to pc and image indoors , this would let you platesove so no need for star alignment  though you still need to polar align using Sharpcap which is very good .

 

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The 2/3 star alignment is only required for visual without the aid of any imaging equipment. The process relies on stars that are low in DEC and far away from each other in order to train the coordinate system on any GOTO mounts. That's why the SynScan hand controller often picks stars that might be blocked by nearby trees and buildings if you have a limited view of the sky.

For imaging once your mount is properly polar aligned (Sharpcap does a great job on that), simply slew to the target with any planetarium software (e.g. Stellarium, CDC) and then plate solve to centre it. Most popular imaging software have plate solver built in (actually they just directly communicate with another dedicated solver such as ASTAP and astrometry.net in the background). The aforementioned APT is one of them. Another popular choice is SGP. Personally I use BYEOS which is a very nice program but only for Canon cameras. If you're comfortable with Linux, you could also try KStars/Ekos with INDI. Ekos provides everything you would need for imaging including capture sequence, plate solving and guiding (although many still prefer PHD2).

Edited by KP82
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