'Bullseye' Error when registering and integrating mosaic images?

Hi Josh @joshfieldsphoto,

How are you trying to make the mosaic? Do you load all the images of all panels and simply register them as a mosaic? Or do you make mosaic panels first with distortion correction and then register the integrated panels as a mosaic?

The reason I ask, is because that result will be caused by a mathematical instability in the way we calculate the dynamic distortion correction. This instability would be caused if you enable dynamic distortion correction when it would not be needed.

I am not 100% sure without seeing your data, so I can also have a look at your data to understand what is happening and fix this behaviour if you want?

Mabula

Hey Mabula, 

That would be great. I am indeed loading the images of all panels and registering as a mosaic. Generally I am doing just 2-3 panels, with significant overlap. I tried integrating each panel before, but could never get those to register afterward for some reason. (I could absolutely be doing that incorrectly as well!)

What interesting is that I almost never change my process, and always use the same equipment, and yet sometimes it works seamlessly, sometimes I get errors like this, and sometimes it doesn't work at all.

In this specific case the focal lengths are slightly different, but I am careful to enter the FL of the reference frame. All past errors were with identical focal lengths. 

In fact, I used these exact images once and it worked fine... I just wanted to try again with some of the images with clouds excluded.

I've uploaded the RAWs to this folder. Files up through 9886 are 24mm, 9900 and up are 21mm. It's a Canon R5 with a pixel pitch of 4.39.

Please let me know if you need anything else, and thank you!

Dear Josh @joshfieldsphoto,

Thank you, can you upload the frames here for me? I checked the google drive folder but it seems to be missing files or isn't it?

https://upload.astropixelprocessor.com/

username: uploadData

password: uploadTestData

Please make a folder with your name and issue like: Josh-bullseye-error

and upload the data there and let me know once done.

I will test your data as soon as possible and will let you know my feedback.

Mabula

@mabula-admin I just uploaded as you requested. Thanks!

Hi Josh @joshfieldsphoto,

Thanks, will test it in the coming days 😉 and will report back later.

Mabula

Hi Josh,

I have tested your data. I have a hard time reproducing the weird issue, but I know it can be the result of different settings in both 3) Analyse Stars and 4) Register, especially the setting 4) register same camera and optics. If you leave it enabled, the issue should never occur. If you disable it, this issue can occur with the current registration module of APP, but if it works, it will be more precise than the one with same camera and optics enabled.

In this case, on your uploaded data, i set 1000 stars target in 3) and in 4) I dsiabled same camera and optics, kept scale stop at 5, enabled dynamic distortion correction and finally mosaic mode:

We have on our todo list, to make this issue go away permantly, but it will require a big update of the registration engine. It will be fixed for sure going forward.

Mabula

Hi Mabula, 

Thanks!

I tried using your settings, even though it gave me lots of warnings about increasing the stop scale for mosaics. I then get the errors below when trying to integrate.

However I tried two more times, and it suddenly worked. 

Is there a go-to setting I should adjust if I get these errors?

Josh

Posted by: @joshfieldsphoto

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Hi Mabula, 

Thanks!

I tried using your settings, even though it gave me lots of warnings about increasing the stop scale for mosaics. I then get the errors below when trying to integrate.

However I tried two more times, and it suddenly worked. 

Is there a go-to setting I should adjust if I get these errors?

Josh

 

@museceleste,

Hi Josh,

It all depends on your data, in this case where I kept scale stop at 5, it means the mosaic was in fact very easy to calculate. Normally, to be safe the scale stop should be as indicated in the warning, scale stop = 10, if it still can not produce the mosaic, you need to increase the scale stop more. The scale stop determines the size of patterns between the stars that APP uses to be able to align/register the images, the higher the scale stop, the smaller the patterns become. It does mean that higher scale stops will only work if there enough stars in those areas where the images overlap, then registration can and will work.

So I might have confused you by setting scale stop at 5, normally set it 10 or higher for a mosaic 😉

Mabula