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N.I.N.A not slewing after platesolving

Stefan Berg Nighttime Imaging 'N' Astronomy (N.I.N.A. / NINA) Plate Solving Troubleshooting
Greisy ValdesScott Badger
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Greisy Valdes avatar
Greisy Valdes avatar
Hello! 
I've been having an issue for 2 nights in a row now where when using the framing assistant in N.I.N.A, the telescope first slews to where it thinks the object is, then it solves the image using All Sky Plate Solver, it says its not within tolerance, it says it "slews" but it just stays in the same place and goes back to imaging and solving. I am not sure what to do, has anyone had this issue before?
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dkamen avatar
dkamen avatar
Greisy Valdes:
Hello! 
I've been having an issue for 2 nights in a row now where when using the framing assistant in N.I.N.A, the telescope first slews to where it thinks the object is, then it solves the image using All Sky Plate Solver, it says its not within tolerance, it says it "slews" but it just stays in the same place and goes back to imaging and solving. I am not sure what to do, has anyone had this issue before?

Hi,

Check that both motors are connected and functional. I get this sometimes with the eqm35 when the cable that connects ra and dec motor isn't plugged well. So it slews on ra but not dec, meaning it will stop slewing once ra error is 0.

You can make sure the motors are ok using the hand controller.
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Padraig Farrell avatar
Padraig Farrell avatar
Yes , I’ve seen that happening a few times. 
Seem’s it caught in a loop, ie: out of tolerance and does another plate solve with the same or little difference in distance error. 
Generally, I’d stop the plate solve when this happens and get the coordinates from framing assistance, put them in manually into my sequence. 
Another thing I do,( if I remember to do ) is slew to the DSO with the planetarium program first and then plate solve. 
Don’t know if this helps ?
Justin Worden avatar
Justin Worden avatar
Is it possible that the tolerance is set too low? For instance if the tolerance set to say 2' and the mount is only able to slew within 3' it will result in a never ending loop of trying to slew to within 2".
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Greisy Valdes avatar
Greisy Valdes avatar
Greisy Valdes:
Hello! 
I've been having an issue for 2 nights in a row now where when using the framing assistant in N.I.N.A, the telescope first slews to where it thinks the object is, then it solves the image using All Sky Plate Solver, it says its not within tolerance, it says it "slews" but it just stays in the same place and goes back to imaging and solving. I am not sure what to do, has anyone had this issue before?

Hi,

Check that both motors are connected and functional. I get this sometimes with the eqm35 when the cable that connects ra and dec motor isn't plugged well. So it slews on ra but not dec, meaning it will stop slewing once ra error is 0.

You can make sure the motors are ok using the hand controller.

Hi, from what I can tell I think they are both connected because I would manually slew using the hand controller or the buttons in NINA and both axes would move. I also gave up thinking it was a NINA problems and went to APT, where I got it to slew and solve correctly, but I tried switching objects in the middle of the night and now it wouldn't plate solve, it would stay looking and looking but would stop because it wouldn't solve it within the time set.
Greisy Valdes avatar
Greisy Valdes avatar
Padraig Farrell:
Yes , I’ve seen that happening a few times. 
Seem’s it caught in a loop, ie: out of tolerance and does another plate solve with the same or little difference in distance error. 
Generally, I’d stop the plate solve when this happens and get the coordinates from framing assistance, put them in manually into my sequence. 
Another thing I do,( if I remember to do ) is slew to the DSO with the planetarium program first and then plate solve. 
Don’t know if this helps ?

*** I did try getting the coordinates from Stallerium, but same issue. It does the slewing sound, and slews just a little bit like when its right on the object but it needs a small tweaking, except that it is not on the object at all, and goes back to solving the same place (which it struggles doing because it takes more than a minute to solve when it would always take seconds, I'm using platesolver 2.28)
Greisy Valdes avatar
Greisy Valdes avatar
Justin Worden:
Is it possible that the tolerance is set too low? For instance if the tolerance set to say 2' and the mount is only able to slew within 3' it will result in a never ending loop of trying to slew to within 2".

I never checked the tolerance settings, I will look into it tonight!
Scott Badger avatar
Scott Badger avatar
Probably a dumb question, but any chance the "Reslew to target" setting got switched to off?
Greisy Valdes avatar
Greisy Valdes avatar
Scott Badger:
Probably a dumb question, but any chance the "Reslew to target" setting got switched to off?

The option to see those settings is grayed out to me, probably because I don't have everything connected but I will try tonight and see, thank you!
Greisy Valdes avatar
Greisy Valdes avatar
Scott Badger:
Probably a dumb question, but any chance the "Reslew to target" setting got switched to off?

I just connected everything and both sync and reslew to target, were off, could that have been it?
Scott Badger avatar
Scott Badger avatar
My understanding is that 'Sync' corrects the mount's model so that it'll slew more accurately for future slews to target, so not critical necessarily, but 'Reslew to target' does need to be enabled for NINA to correct the mount's pointing after a platesolve. The platesolve only tells NINA where the mount is actually pointing. NINA then needs to be instructed (the reslew setting) to calculate the off-set and send the mount where it's supposed to be pointing to.

Cheers,
Scott
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Scott Badger avatar
Scott Badger avatar
BTW, not sure why, but after platesolving it then says 'platesolving' in the bar at the bottom of my screen, as if it's still doing it even though it really isn't…..

Cheers,
Scott
Greisy Valdes avatar
Greisy Valdes avatar
Just an update, I am outside right now, and it is not working. When it plate solves for the first time and says its going to reslew to center the target, it makes the slewing sound but it doesn't slew, I can move the mount both in RA and DEC with no problem with the hand controller and NINA controllers, and if I switch to another target it goes to where it thinks it is, the problem comes to when NINA gives it the command to recenter after plate solving, it's like it's not receiving that command from what I can understand.
Greisy Valdes avatar
Greisy Valdes avatar
Could it be an issue with the plate solver? I am currently using APT and telling it to go to the Pleiades, when it's time to plate solve it just doesn't. It searches through really slowly so it reaches the timeout and just tries again, but obviously fails again. Seems to be two different issues in two different software, this is why I believe is a software issue and not anything wrong with my mount.
Scott Badger avatar
Scott Badger avatar
FWIW, I use ASTAP for platesolving. Sorry it wasn't jus the setting, but that would have been too easy I suppose….. You said it's making a slewing sound but not moving?….

Cheers,
Scott
Greisy Valdes avatar
Greisy Valdes avatar
Scott Badger:
FWIW, I use ASTAP for platesolving. Sorry it wasn't jus the setting, but that would have been too easy I suppose..... You said it's making a slewing sound but not moving?....

Cheers,
Scott

It makes the slew sound but it doesn't slew, it slews every other way tho, just not when NINA tells it to recenter. What I tried in the end was to do a 2 star alignment in my mount using the hand controller, i then asked it to go to IC1848 and it actually went and centered. So i guess I fixed it?? but really I didn’t because I never needed to do that before. I tried it on the Pleiades as well and it did it just fine.
Scott Badger avatar
Scott Badger avatar
Huh……and when I mixed star alignments with my mount and platesolving with NINA, that's when I had centering problems…..

The sound without movement is really odd…..I wonder if it would make that sound and not move if it was getting multiple slew commands that countered each other? Like guiding was still on? But I don't think guiding would be enough to stop it completely….. Anyhow, hope it stays fixed for you. Something about this hobby where on one hand the capabilities of the tools we use, in terms of complexity and precision, is truly amazing, but on the other, just getting everything to power up and connect properly is the biggest win of the night…..

Cheers,
Scott
Marten Amschler avatar
Marten Amschler avatar
can you manually slew it via ASCOM after this problem occurred?

I am asking, because I had the same issue:
  • I set the target coordinates
  • I pressed "slew to target"
  • It roughly went to the first target, started exposing, plate-solved this image, and said it's "not in tolerance"
  • it said slew again but actually didn't move. The next exposure gave the same RA & DEC deviation than the one before
  • it always takes new pictures but doesn't slew in between


the solution to my problem was actually a fault in a cable. Every time the telescope roughly slewed to the target for the first time, the USB-Hub lost connection for short time (maybe due to a loose contact of the cable). And after the USB-Hub regained connection, I would have to restart N.I.N.A to control the mount again....


so, I could fix it with a new USB cable from PC to USB-Hub.

Good luck with finding the root cause of your error
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Gerd Rudolf avatar
Gerd Rudolf avatar
=MsoNormalI have an EQ8 mount and control it via Ascom. The same problem happened to me too. During the corrective movements as part of the plate solving, the mount makes tac-tac-tac noises, but does not move in the desired direction. Up to 10 times in a row, NINA tries to bring the object/star into the middle of the image using plate solving, until I cancel it and center the object manually and resynchronize the coordinates.=MsoNormalI found a solution to the problem in Ascom. I deleted all previous align- and sync data in Ascom and after that the plate solving worked correctly again. Maybe you have a similar problem and can solve it as well. I don't know if this is the basic solution to the problem, it worked for me afterwards.
Greetings from  France
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Carl Svensson avatar
Carl Svensson avatar
I had this issue and solved it by increasing the tolerance, as some have already suggested.
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Greisy Valdes avatar
Greisy Valdes avatar
Carl:
I had this issue and solved it by increasing the tolerance, as some have already suggested.

*How do you increase the tolerance? I am not really sure how to do it in NINA. and I am still sort of having this problem
James Tickner avatar
James Tickner avatar
I don't know if you're using EQmod to control your mount, but if so here's a couple of things to check:

- Make sure in the EQmod page you have the 'dialog based' option selected and not 'append on sync' for the 'user interface' control (located in the Aignment/Sync box). This ensures that each time NINA does a platesolve and sync operation the mount will move the full offset. If you have 'append on sync' selected, EQmod adds more and more sync points to its pointing model and generally undershoots the slew. In extreme cases it doesn't slew at all even though the solved coordinates are off
- If you're using an EQdirect cable to connect directly from your USB port to the RJ-45 port on the mount, it might be worth trying a second cable. I've had issues using older/cheaper cables where the slew commands are only partially received, resulting in the mount 'stuttering' and not moving, or moving only on one axis. Curiously the manual controls work fine, but the slew doesn't.

Good luck! I've been wrestling with similar issues recently and appreciate the frustration.
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Carl Svensson avatar
Carl Svensson avatar
Greisy Valdes:
Carl:
I had this issue and solved it by increasing the tolerance, as some have already suggested.

*How do you increase the tolerance? I am not really sure how to do it in NINA. and I am still sort of having this problem

It's in the NINA Plate Solving Options.  It is called "pointing tolerance."  You can set it to a larger (probably still single digit) number of arcminutes.  For me, the slew was really really close, and it was just looping on trying to get that last little bit, so I was OK with allowing it to be a few arcminutes off, and just end earlier.

https://nighttime-imaging.eu/docs/master/site/tabs/options/platesolving/
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Andy Bulka avatar
Andy Bulka avatar
James Tickner:
- Make sure in the EQmod page you have the 'dialog based' option selected and not 'append on sync' for the 'user interface' control (located in the Aignment/Sync box). This ensures that each time NINA does a platesolve and sync operation the mount will move the full offset. If you have 'append on sync' selected, EQmod adds more and more sync points to its pointing model and generally undershoots the slew. In extreme cases it doesn't slew at all even though the solved coordinates are off

I want to try this advice in order to solve my own repeated "not inside tolerance" messages. I'm not clear on how to answer the EQMOD dialog question "Please confirm that the telescope is pointing at blah..." with the options YES or NO. (P.S. Its cloudy tonight so I can't try this dialog setting, so I'm going by a screenshot I saw in this youtube video on EQMOD at timestamp 5:40s re what the dialog actually looks like when it pops up).

When to answer yes and when to answer no?  In the simulator, I don't get any message popping up actually... hmm.

Surely NINA knows when the plate solve is within tolerance and only sends a sync to EQMOD at that point, and not after every slew?  Actually I find it all pretty confusing.

Update: I've just discovered the official N.I.N.A. EQMOD doco which does indeed say to "Set 'User Interface' to Dialog based". But my question re needing more detail on how this all works and whether any popups appear and how to answer them still stands. Any tips appreciated!
Andy Bulka avatar
Andy Bulka avatar
Update: I've just discovered the official N.I.N.A. EQMOD doco which does indeed say to "Set 'User Interface' to Dialog based". But my question re needing more detail on how this all works and whether any popups appear and how to answer them still stands. Any tips appreciated!

After setting EQMOD with the following (as per the official doco) - which is consistent with the advice by @James Tickner :
  • Run "Setup EQASCOM" and set "Allow site writes" to ON in "Ascom Options"
  • Run "Start EQASCOM" and set "User Interface" to "Dialog based" in "Alignment/Sync"

my plate solving has improved and I no longer get the infinite spiral of being out of tolerance.

I don't think the slews are as accurate as when there are some sync points in the EQMOD point list. After each major slew, I always seem to need to plate solve in NINA and have it do one or two re-slews to get perfectly centered on my HEQ5 (within the default 1 min tolerance).  But I'm happy with that. Who knows, perhaps NINA is indeed just as accurate as my pre-plate solving and "append on sync" days - the plate solving is just raising the bar.  I do wonder if NINA is modelling a points list internally and refining after each slew, or is it just brute force relying on plate solving to be accurate.

P.S. There are no popup dialog box messages with this NINA + EQMOD configuration, despite the implications of such a "Dialog based" setting. Certainly in EQMOD if you click on the dialog box button (that appears when you are set to "Dialog based") you can get a dialog box window to appear for slewing to stars and adding sync points manually, if you are not using NINA. Also, when slewing and syncing from a planetarium program, the youtube video referred to earlier does indeed show a popup message that requires answering, which apparently shifts all the point data for some reason - but even this popup confirmation does not appear in this NINA + EQMOD configuration. So its all seamless for NINA + EQMOD, with no dialogs or popup user interaction, rest assured.
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