×

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

Bi-monthly release with minor bug fixes and improvements

Re:Mosaic tool - overlap not correct on width

  • Posts: 554
  • Thank you received: 138
Tried this with the simulators. A 2x2 mosaic of NGC188 was more or less OK but a 2x2 mosaic of Polaris had Polaris in the correct position but there is a lot or rotation between the images at different right ascensions.
NGC188


Polaris


I think Polaris is a bit too much of an edge case, doing a mosaic generator that can handle that would need a completely different way of working.

BTW these were stacked using ASTAP's Imaging Stitching mode, no pre or post processing, not even darks.
The following user(s) said Thank You: Eric
3 years 8 months ago #56933
Attachments:

Please Log in or Create an account to join the conversation.

  • Posts: 398
  • Thank you received: 117
Just FYI, Jasem didn't apply the pole constraint logic portion of the fragment for the cos(dec) divisor , but the correction that was applied should be good to 89 degrees or better for all FOVs. Depending on whether other parts of the code catch/address angular wrap, any breakdown that might occur would happen at DEC +/- ~89.5 or greater (FOV < 3 degree), and ~89.84 or higher (FOV < 1 degree). This should (hopefully) satisfy pretty much everyone.

Edit: Didn't see Chris' post until right after I posted, but the "flat plane" issue might not be overcome even with a pole wrap constraint.... Interesting results. Nice to see NGC188 works!
Last edit: 3 years 8 months ago by Doug S.
3 years 8 months ago #56934

Please Log in or Create an account to join the conversation.

  • Posts: 1009
  • Thank you received: 133

An edge case yes, but the rotation is already an issue above 60-70 degrees DEC. The mosaic code assumes that the borders stay parallel, but the North direction of course rotates when you move in RA. Unfortunately this isn't solvable properly, unless you have a motorized rotator. Even computing a tiling that doesn't have holes isn't trivial under that condition....
The following user(s) said Thank You: Eric
3 years 8 months ago #57209

Please Log in or Create an account to join the conversation.

  • Posts: 5
  • Thank you received: 0


Is there an easy way of doing this? I use telescopius for planning most of my mosaics...
3 years 3 weeks ago #68098

Please Log in or Create an account to join the conversation.

  • Posts: 1029
  • Thank you received: 301
I'm posting to this thread because I am finishing a rework of the mosaic tool.

I read carefully through your reports and ideas, and I really want to thank you all for everything in this thread, that was very instructive.

I kept the Scheduler job generation the same, except for one change : I calculated the ascension of each tile based on its declination offset from the mosaic center, taking into account rotation. This results in proper RA for large mosaics. Or so I hope, because that's tricky.

I will be posting screenshots and the link to the MR on invent.kde.org. I would be grateful if someone could make a comparison with other tools, in order for me to understand if I got things right.

-Eric
The following user(s) said Thank You: Doug S
3 years 2 weeks ago #68558

Please Log in or Create an account to join the conversation.

  • Posts: 535
  • Thank you received: 109
I just looked through the MR, Eric. I must say I am very excited to try mosaics again! Thank you for the work on this.
The following user(s) said Thank You: Eric
3 years 2 weeks ago #68560

Please Log in or Create an account to join the conversation.

  • Posts: 1029
  • Thank you received: 301
For reference, the MR lives at invent.kde.org/education/kstars/-/merge_requests/241

Thanks for the kind words. I hope I did not introduce a breaking regression by overlooking a detail. There are three elements in the tool: the sky map, the mosaic and the mosaic tile. I did not separate them as cleanly as I'd have liked.

-Eric
3 years 2 weeks ago #68589

Please Log in or Create an account to join the conversation.

  • Posts: 1309
  • Thank you received: 226
Hi Eric. First, let me just say that the overhaul of the Mosaic tool is fantastic. Great work!
I had a thought though. Now that the tool allows for easier framing by moving the frame around, why limit it to strictly generating multi-panel mosaics? I think it can also be very useful for fine positioning a single panel. But the mosaic planner will not allow for single panel jobs to be created.
With that in mind, I would propose allowing it to create single panel jobs. And also renaming the Mosaic tool to something like "Framing and Mosaics" then giving the feature a more prominent position in the scheduler as one of the key steps.
This way when a target is searched for within the scheduler, we can be sure it is framed well.
Thank you!
The following user(s) said Thank You: Eric, Chris Madson
2 years 2 months ago #79280

Please Log in or Create an account to join the conversation.

  • Posts: 1029
  • Thank you received: 301
That's an interesting point, because I remember checking I could use the tool for that exact purpose, single-pane mosaic. However, at that time, the ability to adjust the position was not implemented, so it's possible I missed that issue. A few things can still be improved.

-Eric
2 years 2 months ago #79302

Please Log in or Create an account to join the conversation.

  • Posts: 147
  • Thank you received: 12
I’d echo this. Not to compare the work ya’ll do, but having a single place to frame even single frame pictures would be really helpful. Jumping between the capture tab in ekos to control the rotator and back to kstars is less than ideal.

I’d love an option to turn on and off HiPS within the tool as well. Pulling a hi-res image just for framing is really nice.

Thanks for adding the ‘moving the box around’. That made it much easier!
2 years 2 months ago #79871

Please Log in or Create an account to join the conversation.

  • Posts: 1309
  • Thank you received: 226
Editing mosiac.cpp source code to change the Ok button to enable on line 105, and removing the condition when H and W spinner values are greater than 1 on line 424, allowed me to create a 1 part mosaic job.
105    ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(true);
424    ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(ui->mosaicWSpin->value() > 1 || ui->mosaicHSpin->value() > 1);
Last edit: 2 years 2 months ago by Andrew.
2 years 2 months ago #79874

Please Log in or Create an account to join the conversation.

  • Posts: 147
  • Thank you received: 12
This is harder than I thought it would be to edit... how did you do that? I'm assuming I'll have to compile my own copy.
2 years 2 months ago #79992

Please Log in or Create an account to join the conversation.

Time to create page: 1.030 seconds