Questions about alignment with HEQ5

[AlanP_]

Hi all,

I finally have everything I need for astrophotography, now I just need to learn. I'm a wee bit confused about star alignment however. I think I know how to do polar alignment, but where im confused is star alignment/platesolving.  Do I need to use the synscan controller to do the alignment? All of the tutorials i've watched used that, but my laptop will be connected to the mount via an eqdirect cable. How do I star align directly from the laptop using APT? I may be over thinking it, but the fact that all the tutorials used the synscan controller have me a bit confused.

Another thing I was having a problem with the other night was that I couldn't see the polar alignment outline built into the polar scope of the HEQ5. I did some research and it looks like I might be able to do it through the synscan, but my remote has the 3.28 firmware update and I believe it needs to be a newer version which I dont have the cable for. Is there another way around this?

[Messy Hair 101]

As long as you are polar aligned and your scope is in the home position, I would get rid of the hand controller and just use APT. The alignment procedure will tell your mount it's orientation, platesolving does the same thing so there is no need to do both.

In terms of the polar alignment outline, did you turn your declination axis to 90 degrees so your telescope tube is at right angles to your mount? This will allow you to see the outline.

It's worth looking at this thread to make sure APT is set up correctly for platesolving and save your self a lot of trouble shooting.

There are loads of videos about setting your scope up for the first time, home position and PA. These are old but did the job for me https://www.youtube.com/watch?v=4fO6hyYtPwM

 

 

[StevieDvd]

If you are going the astrophotography route then it's likely you will use a computer to run the process so can use that to Polar Align (PA) too. If you are  going to use a PC then Sharpcap has this included with it's Pro version (£10 a year) well worth a look at the website first and it's a very useful tool for imaging as well. If you intend to use Astroberry, Stellarmate or ASIAir then they all have a software option for Polar Alignment.  And as you mentioned there is a process in the Syncan handset to PA essentially takes you to a star and asks you to centralise the star using the Altitude and Azimuth adjusters of your mount. The process gets repeated a few times until you are happy with the accuracy of the PA and that the goto actions move and centralise your chosen targets.

PA is important as it affects goto accuracy and guiding - but you should soon get the hang of whatever method you prefer.

I tend to think of the star alignment process as a way of telling the mount how to correct any flaws in the goto accuracy and have not done this for quite a while as I rely more on platesolving (and I have a fixed per setup).

Platesolving is where the view from your camera is used by software to calculate where your mount is pointing, and what you are looking at.  Software can be told to synch the mounts co-ordinates of the view with the platesolves co-ordinates (which are usually better).  For example you could have perfect PA and start your session with the mount in it's home position, you tell the software that you are starting in the home position but since this may be done by you moving the mount around after mounting the scope, camera etc it's likely to be slightly off (the home position) PA is still perfect. Now when the software is told to goto a target it moves the mount and thinks it is looking at your target dead centre but it's slightly off. You platesolve and synch and now your software is more accurate, the next goto should be central.

Most of us have a home position (start or park position) usually the weights are down pointing North and the scope vertical.  To a certain extent this is now less important when platesolving. I can turn on my mount move to a target and platesolve it, sych and for that session the software and mount agree - if I ask it to goto home it should return to home correctly.

When you start on the guiding experience platesolving can assist that too. A platesolve & synch before each guiding session can improve accuracy of the mount, after all guiding is a simply an accuracy adjustment done a lot more frequently.

I hope that helps a little but feel free to ask questions we all try to help when we can.

 

 

 

 

 

[AlanP_]

1 hour ago, Messy Hair 101 said:

As long as you are polar aligned and your scope is in the home position, I would get rid of the hand controller and just use APT. The alignment procedure will tell your mount it's orientation, platesolving does the same thing so there is no need to do both.

In terms of the polar alignment outline, did you turn your declination axis to 90 degrees so your telescope tube is at right angles to your mount? This will allow you to see the outline.

It's worth looking at this thread to make sure APT is set up correctly for platesolving and save your self a lot of trouble shooting.

There are loads of videos about setting your scope up for the first time, home position and PA. These are old but did the job for me https://www.youtube.com/watch?v=4fO6hyYtPwM

Ok great, I was worried i'd need to buy another cable!

Yeah, I can see the outline in daylight right now and I was testing it with a chimney in the distance to get a feel for it, but I am pretty sure theres an led that can be turned on which I think needs that firmware update. Thanks for that link too.

39 minutes ago, StevieDvd said:

If you are going the astrophotography route then it's likely you will use a computer to run the process so can use that to Polar Align (PA) too. If you are  going to use a PC then Sharpcap has this included with it's Pro version (£10 a year) well worth a look at the website first and it's a very useful tool for imaging as well. If you intend to use Astroberry, Stellarmate or ASIAir then they all have a software option for Polar Alignment.  And as you mentioned there is a process in the Syncan handset to PA essentially takes you to a star and asks you to centralise the star using the Altitude and Azimuth adjusters of your mount. The process gets repeated a few times until you are happy with the accuracy of the PA and that the goto actions move and centralise your chosen targets.

PA is important as it affects goto accuracy and guiding - but you should soon get the hang of whatever method you prefer.

I tend to think of the star alignment process as a way of telling the mount how to correct any flaws in the goto accuracy and have not done this for quite a while as I rely more on platesolving (and I have a fixed per setup).

Platesolving is where the view from your camera is used by software to calculate where your mount is pointing, and what you are looking at.  Software can be told to synch the mounts co-ordinates of the view with the platesolves co-ordinates (which are usually better).  For example you could have perfect PA and start your session with the mount in it's home position, you tell the software that you are starting in the home position but since this may be done by you moving the mount around after mounting the scope, camera etc it's likely to be slightly off (the home position) PA is still perfect. Now when the software is told to goto a target it moves the mount and thinks it is looking at your target dead centre but it's slightly off. You platesolve and synch and now your software is more accurate, the next goto should be central.

Most of us have a home position (start or park position) usually the weights are down pointing North and the scope vertical.  To a certain extent this is now less important when platesolving. I can turn on my mount move to a target and platesolve it, sych and for that session the software and mount agree - if I ask it to goto home it should return to home correctly.

When you start on the guiding experience platesolving can assist that too. A platesolve & synch before each guiding session can improve accuracy of the mount, after all guiding is a simply an accuracy adjustment done a lot more frequently.

I hope that helps a little but feel free to ask questions we all try to help when we can.

Does sharpcap require a guide camera to do PA?

Yeah, I think that I want to use platesolving as it seems to be a really nice tool. 

Thanks a lot for that information, im sure ill have other questions when the clouds part again!

[StevieDvd]

I guess so many people are now doing PA without using a polarscope that it's hard to find how to align it, I know I just searched but I did find this  https://www.myastroscience.com/polarscopecalibration 

The aim is to be able to rotate the mount and keep the centre cross hair centred on the target (aerial, chimney - don;t recommend pigeons they move).

Yes you will need a camera to use Sharpcap PA - either in the telescope or you can use the guide scope.  The camera does not need to be central like the polarscope, just needs to be firmly attached.  See https://www.sharpcap.co.uk/sharpcap/features/polar-alignment

Do your reading whilst it's cloudy 🙂

[AlanP_]

1 hour ago, StevieDvd said:

I guess so many people are now doing PA without using a polarscope that it's hard to find how to align it, I know I just searched but I did find this  https://www.myastroscience.com/polarscopecalibration 

The aim is to be able to rotate the mount and keep the centre cross hair centred on the target (aerial, chimney - don;t recommend pigeons they move).

Yes you will need a camera to use Sharpcap PA - either in the telescope or you can use the guide scope.  The camera does not need to be central like the polarscope, just needs to be firmly attached.  See https://www.sharpcap.co.uk/sharpcap/features/polar-alignment

Do your reading whilst it's cloudy 🙂

Thanks Steve. I tested my polar scope and it was surprisingly well calibrated. It did move ever so slightly, but it really was miniscule and I didnt want to touch it anymore - i'd probably do more harm

I do want to get a guide camera down the line, but i'd rather learn the basics first before I get too deep into it. I've setup platesolver in APT and now its just a matter of getting out there! Sunday night seems promising weather wise.

Another question, my garden is south facing and the only area with polaris in view is up near the top of the garden. However, it means I sacrifice a lot of the sky on the west with Orion and pliedies barely in view. A much better view is right at the start of my garden, but then polaris is out of view. Do I need polaris in view to properly do deep sky astrophotography? 

[StevieDvd]

17 hours ago, AlanP_ said:

Another question, my garden is south facing and the only area with polaris in view is up near the top of the garden. However, it means I sacrifice a lot of the sky on the west with Orion and pliedies barely in view. A much better view is right at the start of my garden, but then polaris is out of view. Do I need polaris in view to properly do deep sky astrophotography? 

You can polar align without a vew of Polaris, it justs limits the methods since as a lot of the easier ones use a view with polaris.  Essentially if you can plate solve a few images or 'eye solve' this will give the tool where your current mount axis is pointing for it to work out the adjustment you need to correct it.

1. Your handset routine has a PA correction option.  That uses the 'eye solve'  and uses an iterative process of it telling you to centre the goto selection it makes.

2. Some software tools can do the calculations and don't use a Polaris view.  I believe APT has one and there is one in Ekos (Linux) to name a couple.