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INDI Library v1.8.1 Released (09 Sep 2019)

Monthly maintenance release INDI v1.8.1

Polar alignment... what am I missing

2 months 2 weeks ago
Vox45
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Polar alignment... what am I missing #42851
Hello All ! I need your collective knowledge to solve an issue that is really bugging me :)

I tried the PA method using astronmetry and I constantly get a 1°+ error on PA even though I follow the steps as I think they are to be followed. I need some help to figure out what I am doing wrong.

-> I use my guide scope ( instead of using my scope with a DSLR) to do the PA routine as it has a large FOV and refreshes quickly
-> plate solving is successful on each attempt
-> when I get to the final screen, I double click on a star in the field to get the correction vector's crosshair

(It took me a while to understand what was happening as I was only "clicking" on a star as it is instructed but only clicking once only moves the purple line to the star but does not show the crosshair...)

-> I then move the star to the center of the crosshair using the lat and long bolts on the mount

-> I did this multiple time and still I get a 1° error every time

Here are 2 screen shots that may help understand what I did. Am I misunderstanding the procedure ?





Please let me know :)

"Some people are so poor, all they have is money"
SW Black Diamond 80ED | SW150MAK | Newton SW 200/1000 | Orion 50mm Guider with Helical Focuser |Sirius EQ-G Rowan Belt Mode
Canon 1000D moded | ZWO ASI185MC | Baader Mark III Zoom
INDI | Stellarmate on RPI3B+ | Stellarium | Pixinsight
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2 months 2 weeks ago
Herrhausen
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Polar alignment... what am I missing #42878

Vox45 wrote: -> when I get to the final screen, I double click on a star in the field to get the correction vector's crosshair

(It took me a while to understand what was happening as I was only "clicking" on a star as it is instructed but only clicking once only moves the purple line to the star but does not show the crosshair...)


Oh wow, thanks for pointing this out! I assume that's why I failed to succeed when I once tried the PA procedure.

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2 months 2 weeks ago
andefeldt
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Polar alignment... what am I missing #42884

Vox45 wrote: -> when I get to the final screen, I double click on a star in the field to get the correction vector's crosshair

(It took me a while to understand what was happening as I was only "clicking" on a star as it is instructed but only clicking once only moves the purple line to the star but does not show the crosshair...)


Wow! It's also news to me that you need to double click a star. I always just end up with a purple line, but no crosshairs (except the first time I tried - maybe I double clicked by accident then?) so I haven't been able to PA correctly yet. I'll give the double click a try next time.

If your PA error is too large afterwards, then just try and redo the process. This should help improve the PA - I guess.

Anders

SkyWatcher ED80 Pro
Skywatcher HEQ5 Pro with Rowan Belt Mod with EQDIR cable
ZWO ASI294MC Pro imaging camera
QHY5L-II-C guide camera on 50mm guidescope
DeepSkyDad AF3 autofocuser
Controlled from Kstars/Ekos on Mac

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2 months 1 week ago
Vox45
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Polar alignment... what am I missing #42885
Yes I was surprised myself the first time I saw the crosshair appear as I've been looking for it for quite a while ... It would be nice to update the instruction to point this out ;)

I did the PA routine multiple time and always end up with the same error. Now, could it be that because I use my guide scope and that the guide scope is mounted on the side of the OTA that it would induce a shift in the PA result. It does say in the screen shot that the mount axis is to the bottom left of the NCP...

Anyone knows of a video where we can see the whole procedure ? There is one by Jasem that is a bit dated and we don't see the actual crosshair alignment part...

"Some people are so poor, all they have is money"
SW Black Diamond 80ED | SW150MAK | Newton SW 200/1000 | Orion 50mm Guider with Helical Focuser |Sirius EQ-G Rowan Belt Mode
Canon 1000D moded | ZWO ASI185MC | Baader Mark III Zoom
INDI | Stellarmate on RPI3B+ | Stellarium | Pixinsight

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2 months 1 week ago
Ihoujin
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Polar alignment... what am I missing #42886
It does not matter that the objective use for alignment is to one side. It will still share a common center of rotation at infinity. You may be dealing with differential flexure, cable snags, or bad backlash on the worm causing the OTA alignment to shift slightly at different position. Also missing crosshair or need to double click is news to me, odd.

INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
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Orion SSAG @280mm Guide Scope
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Adafruit Motor Hat shield
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Startech 7 port powered USB Hub.

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2 months 1 week ago
andefeldt
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Polar alignment... what am I missing #42895
Ok, I just tried the PA tool in the simulator. That shows the crosshairs right away. Clicking a star moves the purple line and crosshairs to the new location. When double clicking a star, the crosshairs moves to the star in the other end of the purple line. So I don't think you are supposed to double click a star?!

SkyWatcher ED80 Pro
Skywatcher HEQ5 Pro with Rowan Belt Mod with EQDIR cable
ZWO ASI294MC Pro imaging camera
QHY5L-II-C guide camera on 50mm guidescope
DeepSkyDad AF3 autofocuser
Controlled from Kstars/Ekos on Mac

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2 months 1 week ago
Vox45
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Polar alignment... what am I missing #42897
That is interesting. Would that mean when I was only clicking once it was showing the crosshair on the other end of the purple line but I could not see it as it was off screen ? If so, what is the purpose of bringing the crosshair to the other side of the purple line when clicking twice ? As you can see in the screen shot I was centered in that crosshair but the alignment is out by 1° ... This is odd

"Some people are so poor, all they have is money"
SW Black Diamond 80ED | SW150MAK | Newton SW 200/1000 | Orion 50mm Guider with Helical Focuser |Sirius EQ-G Rowan Belt Mode
Canon 1000D moded | ZWO ASI185MC | Baader Mark III Zoom
INDI | Stellarmate on RPI3B+ | Stellarium | Pixinsight

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2 months 1 week ago
andefeldt
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Polar alignment... what am I missing #42900

Vox45 wrote: That is interesting. Would that mean when I was only clicking once it was showing the crosshair on the other end of the purple line but I could not see it as it was off screen ? If so, what is the purpose of bringing the crosshair to the other side of the purple line when clicking twice ? As you can see in the screen shot I was centered in that crosshair but the alignment is out by 1° ... This is odd


All the times I've tried to PA I could only see the Purple line across the entire FOV. When moving as far as possible along the line and then redoing the PA to get even closer, I was told be Ekos that the NCP was outside my FOV, eventhough I should've been closer than my initial PA. When the weather clears (should be within the next decade or so :) ) I'll give it a try again and double clicking this time (I've moved from running KStars/Ekos on my Mac to running it on a Raspberry Pi 4, but haven't had a chance to test it yet).

I think we need some of the developers to look at the thread. Maybe they can tells us about the double click etc.

Anders

SkyWatcher ED80 Pro
Skywatcher HEQ5 Pro with Rowan Belt Mod with EQDIR cable
ZWO ASI294MC Pro imaging camera
QHY5L-II-C guide camera on 50mm guidescope
DeepSkyDad AF3 autofocuser
Controlled from Kstars/Ekos on Mac

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2 months 1 week ago
Ihoujin
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Polar alignment... what am I missing #42906
There are reasons why the ncp will not be in frame and it is not the be-all-end-all. It could just be cone error, or slight Dec misalignment from when you setup the home position.
If was you day is true and double click moves the crosshair, it could be for those in the southern hemisphere.
I've only ever clicked once, and brought the star to the end of the line where my crosshair is.

INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.

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2 months 1 week ago
knro
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Polar alignment... what am I missing #42908
so double clicking in any FITS viewer image would center the crosshair around that point. I just added code to disable this when polar aligning to prevent confusion. Should be in 3.3.5

Jasem Mutlaq
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2 months 1 week ago
Vox45
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Polar alignment... what am I missing #42910
So just to make sure I understand:

I could not see the crosshair because I was way out of range ( the 1° error was accurate then) it was actually at the other end of the purple line (?) Just moving along the line should show me the crosshair and then, once I see it, I just click once on a star near that crosshair and center it into the crosshair ?

"Some people are so poor, all they have is money"
SW Black Diamond 80ED | SW150MAK | Newton SW 200/1000 | Orion 50mm Guider with Helical Focuser |Sirius EQ-G Rowan Belt Mode
Canon 1000D moded | ZWO ASI185MC | Baader Mark III Zoom
INDI | Stellarmate on RPI3B+ | Stellarium | Pixinsight

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2 months 1 week ago
Ihoujin
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Polar alignment... what am I missing #42925
If you can not fit the line in your FOV, you will have to do it more than once gradually reducing the error.
You will be clicking on a suitable reference star. It should be bright enough to easily distinguish while in the image refresh step. If you begin the refresh cycle and can not clearly see your chosen star, either increase the exposure time or select a new star. Do not select a new star once you've begun making adjustments. While refreshing, adjust your Alt/Az bolts and follow the reference star and attempt to bring it to the end of the line where the crosshair resides.

INDI/KStars on Raspberry Pi 3B+
Lubuntu 16.04
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG @280mm Guide Scope
PHD2
Adafruit Motor Hat shield
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
The following user(s) said Thank You Vox45

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