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INDI Library v1.9.2 Released (14 Sep 2021)

Bimonthly Stable INDI Library release introduces new drivers and fixes for existing ones.

Re:New Polar Alignment Scheme and Features

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If your mount begins the PA routine from the Park (or Home) positions, then, when you come to see the correction vectors, the scopes have rotated by 60° to the West (or East). Therefore Alt and Az mechanical adjustments will move the chosen star along lines which are 60° rotated from vertical and horizontal on your display. If you want to avoid this you should start the PA process from a pre-rotated start position 60° to the East (or West). I have tried this, but in the end I've just accepted that the green and yellow vectors are the directions of the Alt and Az adjustments. ,
Currently running KStars/Ekos/Indi on two Raspberry Pi 4Bs 4GByte under Raspberry Pi OS thanks to Astroberry
Two mounts, two Fracs, a Newt and a Mak and a couple of OSC cameras.
5 months 4 weeks ago #69009
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Alex,

Could you explain a little more? You say your star follows the purple line when you're correcting polar alignment. Is that with the Alt knob, or the Az knob, or both? If you're pointed somewhere near the pole, those two knobs should move your telescope is orthogonal directions, so it would be surprising that they both move the star along the purple line.  If almost all of your alignment error is in one of the axes, then moving the offending knob, would, of course be pretty similar to the purple line.

As an experiment, you might intentionally misalign both axes by, say, 20 or 30 arc-minutes and see if you still get the same behavior.

FWIW, at least for my setup, I don't believe the numbers much for anything under 1 arc-minute, or perhaps half that. I wouldn't recommend thinking about arc-seconds. 

Thanks for trying it out,
Hy
 
Orion Atlas Pro, William Optics ZS105, Moonlight V2 focuser
ZWO ASI1600, OAG & Filterwheel, Astronomik Filters, QHY 5L-IIm guidecam.
KStars/Ekos/Indi on RPi4 w/SSD
Ekos Projects: Terrain Backgrounds, Polar Alignment, Analyze, Linear Focuser, SEP MultiStar & GPG Guiding, FITS autostretch.
5 months 4 weeks ago #69024
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Hello Hy,

Sorry, I was not clear in my description of what I think is the problem. I (myself) try to follow the purple line to the crosshair and use both knobs for this. So the workflow for me is basically like in the previous version. The movement of the Alt and Az knobs itself is at least close to orthogonal. So with a bit of trial and error I make my way along the purple line using the knobs for Alt and AZ.

With the split into Alt and AZ components in the display that you implemented  my expectation was that I could use this decomposition of the Alt and Az component for the correction. So when I select a star I expected to move only Alt along the yellow line to the edge of the triangle, then only Az along the green line to the crosshair. So only care about one direction at a time. But when moving my Altidude screw on the mount the stars do not move parallel to the yellow line. Same applies to AZ not parallel to the green line.

Wrong expectation that I could move the selected star along the indicated lines, separating the Alt and AZ correction? Do I need to slew back to home before using the hardware knobs as the calculation of the vectors is based on the first position?

Thanks!
Alex

In case this is relevant: I start in the home position and slew 30 degrees east with each step so when I start turning the hardware knobs the mount is rotated by 60 degrees. I could see Polaris from where I set up my mount and start close to the pole. At the moment I use my main scope for the polar alignment(432 mm focal length, camera ASI 533MC). I'm not  striving for extreme precision below an arcminute.
Standard setup: EQ6R, Williams Megrez 72- ASI 533MC -ZWO EAF, 50 mm viewfinder - ASI 120MM
5 months 4 weeks ago #69030
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Hi,

could it be your mount is not level? You can perfectly polar align in case it is not level, but an adlustment in AZ will have impact on Alt. Looks like that is what you are describing?

Rgrds,

Paul
5 months 4 weeks ago #69031
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Paul,
I use the bubble level of the mount and align the bar with the double clamp with an electronic level. Might not be perfect but I assume it is not too far off.

Potentially anything to do with the fact that the clamp of the scope itself is turned by 90 degrees for fixing the bar? Do I need to enter this in some configuration setting?

Alex

Gesendet von meinem BKL-L09 mit Tapatalk
Standard setup: EQ6R, Williams Megrez 72- ASI 533MC -ZWO EAF, 50 mm viewfinder - ASI 120MM
5 months 4 weeks ago #69033
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I was using this feature last night in the northern hemisphere and doing a polar alignment away from the pole. I found the correction vectors recommended wherein the wrong direction. Also adjusting say Altitude the star never travelled along the yellow line or anywhere near it. So what I ended up doing was looking at the length of each vector and then moving the star that length for the corresponding direction.
I am using a Celestron AVX mount connected via HC and a 6 " RC scope with an AA26C camera. KSTARS is 3.5.2 stable build.
Is there something I need to check or configure to correct this performance?

Thanks
Lenny
5 months 2 weeks ago #69572
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Do you have any logs? Hy is working on this issue and he suspects its due to image parity as reported by the solver. The log would confirm this.
Jasem Mutlaq
Support INDI & Ekos; Get StellarMate Astrophotography Gadget.
How to Submit Logs when you have problems?
Add your observatory info
5 months 2 weeks ago #69576
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As the problem that I experience is somewhat similar to what LKIERSEY  describes (when turning the knobs on my EQ6R the movement of the stars is not alligned to the vectors displayed): what log should be activated to be able to record helpful input here? The weather might allow me to have a session in the next days so I might be able to get some data that might be valuabe to help to narrow it down.

Alex
Standard setup: EQ6R, Williams Megrez 72- ASI 533MC -ZWO EAF, 50 mm viewfinder - ASI 120MM
5 months 2 weeks ago #69578
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Sorry Jasem, I had no logs enabled last night. Will be trying again tonight.
5 months 2 weeks ago #69583
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There is a way to add a little delay betwen the slews and the capture? actually it is to fast and there is no time when the capture start form the end of the slew
5 months 2 weeks ago #69586
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ALESSANDRO @Alessandro: Yes, you can add delay between slew and capture with the "Settle" setting (below "Accuracy", to the right of the Declination display in the upper left)
 
Orion Atlas Pro, William Optics ZS105, Moonlight V2 focuser
ZWO ASI1600, OAG & Filterwheel, Astronomik Filters, QHY 5L-IIm guidecam.
KStars/Ekos/Indi on RPi4 w/SSD
Ekos Projects: Terrain Backgrounds, Polar Alignment, Analyze, Linear Focuser, SEP MultiStar & GPG Guiding, FITS autostretch.
The following user(s) said Thank You: ALESSANDRO PENSATO
5 months 2 weeks ago #69605
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Sorry I found it after that I wrote the post. At this time I am going out of mind with my EQ6 mount that is not stable on the tripod base, I can't lock it after each azimuth correction during the polar alignment procedure
5 months 2 weeks ago #69606
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