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INDI Library v2.0.6 is Released (02 Feb 2024)

Bi-monthly release with minor bug fixes and improvements

Ekos Polar Alignment Assistant (Beta) is here!

Gooood news everyone!

I just tested the Ekos Polar Alignment Assistant (Beta) with my mount, and it works great!! It's still early beta tool, but this is the tool you asked for! It's light years ahead of the previous polar alignment measurement and correction (now called legacy) tool.

I used ZWO ASI120M on Orion 50m 170mm Focal length guide scope to do this. You need a relatively wide FOV of 1 degrees or more for this to work since the astrometry.net solver has a really bad time solving anything small. I started the process by capturing two images, which after quite a it of spherical trig math, you end up with 2 points + radius --> two circle solutions for mount RA Axis. Problem was trying to figure out which one of those solution is the correct one. So there was more math nasty math involved and I tried looking for other solutions. Gary suggested I use 3 points (hence 3 images) so that you can define a unique circle, and that worked quite well. I guess with astrometry, one extra image for increased accuracy wouldn't hurt.

I'm going to write a complete guide (I am updating Ekos documentation now) + make a video, but you can give it a go from the PPA starting from tomorrow hopefully. So with ZWO + Orion Guide Scope, I had to fix a few things:

1. Solved a few images and found that the "real" focal length was around 174m and not 162.. of course it makes sense due to the placement of the camera in the tube. So I had to correct this value in the guide scope settings.
2. Had to fine-tune quite a few parameters in the ASI120m to get a decent image that would solve. Ended up with 40% gain + RAW 8 (Luma was too noisy). Point is, you need decent images with few stars that can get solved.

The tool can be automated and it ends up drawing the correction vector. You can move the vector anywhere in the image (hopefully to some bright star) and then move that star into the crosshair and viola, done! I'd like to thank Robert Lancaster as well for his awesome work on the Equatorial Gridlines which made developing this tools much easier and for his constant very useful feedback.

Try to give this tool a go and let me know what you think.
The following user(s) said Thank You: Gonzothegreat, pauledd, Pepe, nMAC, Radek Kaczorek, gehelem, Philippe, Schreiber, Vincent Groenewold, Magnus Larsson and 6 other people also said thanks.
7 years 1 month ago #14381
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Wow great feature Jasem! Thanks!
I need to remake my polar alignment, will test it when possible for sure.

One note: Those are the settings I am using with my ASI120MM and were the ones that gave me a cleaner image.
I get 162mm focal length with my Orion Finder because I am using a special adapter (custom made) to camera that keeps the focal length as specified.
Last edit: 7 years 1 month ago by nMAC.
7 years 1 month ago #14382
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This sounds very promising! Although I hope something can be done with the FOV limitations.
Myself I have the ZWO guidescope F/4.6 (60mm/280mm). This works out to be an FOV of 58.9' x 44.2'. So not quite a full degree across.

How long of a delay is there between the frames? Since you are aiming at the celestial pole, there would only be a slight shift over time compared to near the meridian and celestial equator.
7 years 1 month ago #14385
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Strange, I never had any problems with astrometry solver. If you preselect the right index file for you fov in the astrometry.cfg instead of letting astrometry try all index files I got solving done in almost less that 3 seconds + some extra time for the very first solving until astrometry has read the index file into ram. But I can only confirm this down to FOV: 1.28° x 0.85°

Its not very clear to me how the new "Ekos Polar Alignment Assistant" works. Can you give a short explanation?
From what I understand is that you point a scope (Guiding Scope? would the teleskope itself work too?) to polaris, near polaris, somewhere north? Then you run the routine and align the mount with the Alt/Az bolts to match the star position in the image that was calculated. Is that right?
Would it be possible to use the main tube to do the alignment? For example If one does not own a guide scope?
--= human, without Windows™ =--
pls excuse my bad english! :)
7 years 1 month ago #14423
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Here it is:



It would be possible to use your primary scope. I could turn off the 1-degree requirement to allow for testing and see if that works. However, correcting the mount error in a small FOV is also challenging nevertheless.

EDIT: Ok I made it 30 arcminutes, so we'll see if it can work with that. It didn't on my system and I have > 50 arcmins FOV.
The following user(s) said Thank You: Keith Cobby, Chris Ryan, pauledd, Paolo Casarini, Rob Lancaster, julian J griffiths
Last edit: 7 years 1 month ago by Jasem Mutlaq.
7 years 1 month ago #14431
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Thanks for the nice video! My questions are gone.

Edit:
My primary scope has a fov of 140x93 arcmin so that should work, I can hardly wait to test it :silly:
--= human, without Windows™ =--
pls excuse my bad english! :)
Last edit: 7 years 1 month ago by pauledd.
7 years 1 month ago #14432
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Hi Jasem

Fantastic new feature, that has been awaited for a long time, thanks a lot :-)

With my current setup, I have a FOV of 1.15° x 0.86° on my guide-scope (TS Deluxe 60mm Guide Scope, 240mm focal length + ZWO ASI 120MM).
So I guess it would work with the limitations of the Astrometry.net solver.

However, I've already invested in the QHY CCD Polemaster, in order to make my polar alignment routine fast and easy.
Sadly it only works on Windows (and Mac, in a beta version).
I would very much like to re-use the polemaster camera itself, on linux, but with the EKOS software...

So I'm now wondering if anyone have had any luck getting the polemaster camera to work on linux???
If not, are there anybody who could give me some pointers on how to get it to run...? I've tried with gphoto2, but so far with no success.

Ubuntu detects the camera, but doesn't recognize it, so I guess it doesn't load any driver for it...

dmesg log look like this:
[ 2532.439768] usb 2-1.2: new high-speed USB device number 7 using ehci-pci
[ 2532.532485] usb 2-1.2: New USB device found, idVendor=1618, idProduct=0940
[ 2532.532496] usb 2-1.2: New USB device strings: Mfr=0, Product=0, SerialNumber

lsusb -t output:
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 480M
    |__ Port 1: Dev 2, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M
        |__ Port 2: Dev 7, If 0, Class=Vendor Specific Class, Driver=, 480M     <- (this is the QHY CCD Polemaster camera)
        |__ Port 4: Dev 3, If 10, Class=CDC Data, Driver=cdc_acm, 480M
        |__ Port 4: Dev 3, If 0, Class=Communications, Driver=, 480M
        |__ Port 4: Dev 3, If 1, Class=Communications, Driver=cdc_acm, 480M
        |__ Port 4: Dev 3, If 2, Class=CDC Data, Driver=cdc_acm, 480M
        |__ Port 4: Dev 3, If 3, Class=Communications, Driver=cdc_acm, 480M
        |__ Port 4: Dev 3, If 4, Class=CDC Data, Driver=cdc_acm, 480M
        |__ Port 4: Dev 3, If 5, Class=Communications, Driver=cdc_wdm, 480M
        |__ Port 4: Dev 3, If 6, Class=Communications, Driver=cdc_ncm, 480M
        |__ Port 4: Dev 3, If 7, Class=CDC Data, Driver=cdc_ncm, 480M
        |__ Port 4: Dev 3, If 8, Class=Communications, Driver=cdc_wdm, 480M
        |__ Port 4: Dev 3, If 9, Class=Communications, Driver=cdc_acm, 480M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M
        |__ Port 4: Dev 3, If 0, Class=Wireless, Driver=btusb, 12M
        |__ Port 4: Dev 3, If 1, Class=Wireless, Driver=btusb, 12M
        |__ Port 4: Dev 3, If 2, Class=Vendor Specific Class, Driver=, 12M
        |__ Port 4: Dev 3, If 3, Class=Application Specific Interface, Driver=, 12M
        |__ Port 6: Dev 4, If 0, Class=Video, Driver=uvcvideo, 480M
        |__ Port 6: Dev 4, If 1, Class=Video, Driver=uvcvideo, 480M
Last edit: 7 years 1 month ago by Anders Lange.
7 years 1 month ago #14440
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You'll have to directly contact QHY to request support, it's not supported by the SDK. Also, even if the camera works, you would still need software for polar alignment, so most likely you'd be using Ekos PAA
7 years 1 month ago #14445
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Hi Jasem

I definitely intend to be using the Ekos PAA. I would just like to be able to do it using the Polemaster hardware, so my investment in this piece of equipment hasn't been invain ;-)

I'll try to contact QHY to see if they will be able to provide a linux device driver for the camera.
7 years 1 month ago #14457
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I am in the same situation (Polemaster owner, wanting to use it with new polar align software advertised here).
I have posted on the QHY forum.

Kevin
7 years 1 month ago #14460
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So far so good, I am very impressed by this feature. It does crash a lot but this is a beta version. They issue i have is now my fits images are very green, using a can 40D, before the colours were good, now very green.

Keep up the great work.
7 years 1 month ago #14461
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KStars Options --> Advanced: Turn off both Auto Debayer & 3D Cube. If there is crash, please submit GDB backtrace as per instructions in my signature. Thanks for testing it!
7 years 1 month ago #14462
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