Polar Alignment via Platesolving

[Jean-Francois]

Hello Robin,

OK, I used the time.sleep() and it works fine.

I have no error "Object reference ..." with the script from the IronPython console after waiting, but the error appears every time with the "menu" version.

The question of the good timing is not easy ... too much different configuration.
It is possible after the end of the MoveAxis() of the mount to wait several exposure.
But how many is sufficient and it comes quick too many can have a long waiting time.
If the exposure is only 0.5 or 1.0 seconds ... not a problem, but it is different with 5 or 10 seconds.
If you wait 2 or 3 exposures ... then it will be quick 20 or 30 seconds for only waiting.

In the meantime, I found the errors in my script. Now it calculates the difference correctly.
I think I will wait until the weekend before I upload it.
Until now only 2 downloads of my script ... one was from me and the other from you.

Regards,
Jean-Francois

[akjudge]

I'm watching and waiting for the final script before downloading. Thanks again

Jim

[admin]

Hi,

SharpCap already has configuration options to set a settling time for mount movements - you can recover the time that is configured via

Code: Select all

SharpCap.Mounts.SelectedMount.SettleTime.TotalSeconds

That gives you an idea of how long to wait after asking the mount to stop moving (and the user can adjust the settings if it is not long enough). Beyond that, I would wait one exposure time if the camera is in live mode, then select the next frame after that. Except in the annoying case of cameras that buffer extra frames, that should be fine.

cheers,

Robin

[Jean-Francois]

Hello,

Thanks for the command about the settling time.
I was planning to use it for the movement from the West point to the meridian where the RA tracking will have some backlash.
In the other direction from the East point to the meridian, in principle no backlash while already in the RA tracking direction.

For waiting an image ... my script function CaptureFrameHandler() already does it for 2 images.
But I remark now that it is not doing exactly what I was expected.

Regards,
Jean-Francois

(I'm "blocked" in Newbury until Sunday because of the strike of Lufthansa.)

[Jean-Francois]

Hello Robin,

Where is the function SharpCap.Mounts.SelectedMount.SettleTime.TotalSeconds ?
I use for my tests the GSS Simulator.

Maybe in the past ... but not found in the last SharpCap version ...

Mount_settle_time_1.jpg (27.28 KiB) Viewed 430 times

Mount_settle_time_2.jpg (21.15 KiB) Viewed 430 times

Jean-Francois

[admin]

Hi Jean-Francois,

oops, sorry, it's on the internal API that I use, but not on the scripting visible part of the API. I will fix that for the next 4.1 update.

cheers,

Robin

[admin]

Hi,

as I was adding the settle time property, I spotted that there is an existing 'IsSettled' property that you should be able to access - this should actually be simpler to use, as you just need to finish your movement and then wait for IsSettled to become true.

cheers,

Robin

[Jean-Francois]

Hello Robin,

thanks for doing the SettleTime function accessible from the script.

I saw the "IsSettled" yesterday too ... yes, it could be an alternative.
If all the mounts behave as expected. in the other hand, wait a predefined time is more sure.

Jean-Francois

[Jean-Francois]

Hello,

I have now a new version ... here: viewtopic.php?p=52608#p52608

I tested it during the last weekend.
It was working properly, but I need to improve the manual process.
The full automatic is working fine. The last version shows now the stars from the Plate Solve (note from the last selected index of SharpSolve).

The use of my script is now the following:

- change the coordinate of your location from the [...] button and the air conditions
- you can tune the starting point (Alt-Az coordinates) and the end point (degree relative to the meridian line, + is further and - is before the meridian)
- in automatic mode ... click on "Alignment" for starting the alignment steps. But now you can move the telescope to a new position before starting the alignment steps. That means first move to a new position near the meridian and then click on "Alignment" button. That is necessary for the people with a fork ... it is possible to have near 180° rotation, but it is necessary to perform the alignment steps near the meridian.
- the numerical values are in [degrees] ... 1 arcmin = 0.0167 and 10 arcsec = 0.0028 (0.01 is good, 0.001 is very good and 0.0001 your are the king!)
- the script works in Live View or in Still mode, but the plate solve stars are not shown in Still mode (maybe I will found a way to show the stars).

One time again a warning ... the script uses the MoveAxis() command. That means that the mount stops only if it receive a command to stop.
So, you need a very reliable computer-mount connection. Do not use my script with a WiFi connection to the mount !

Jean-Francois

[Jean-Francois]

Hello Robin,

I did yesterday night more tests with real sky and camera. That is a difference to the Sky Simulator.
In the Sky Simulator, you have no smearing or other vibration on the images

That is a problem (to solve) in my script. During the alignment process, Plate Solve is done continuously.
But sometimes the images is so bad, that no solution is found ... and my script is blocked.

How can I check a valid result or cancel a Plate Solve in a script (if it takes too long) ?
It is possible to "Cancel" a Plate Solve with the "Cancel" button from the annotation ... but how to communicate to the script that the Plates Solve has been cancelled manually ?


Regards,
Jean-Francois