halo after integration and very, very grainy

Wow, never seen that before. How do your calibration frames look? And how does a single sub look like?

@vincent-mod

This is very strange.  I don't think my previous reply went through.  I had five sets of data to process.  All using the same calibration frames.  The first three were fine.  no issues.  It was this one that produced the worse.  This morning I processed the final set and did not have the same artifacts but had different artifacts are stars and brighter portions of the nebula.  

I'm really wondering if I tweaked a setting that is being retained and I should just reset.  Is there a way to reset all the settings back to "factory default" and I try again?

Thanks

Well, as APP doesn't have stored settings, just the "factory settings" it's already there each time you start. Saving the settings will come in a future update, but in your case that's not the problem. This must be in the data, I can have a look if you want. You can share you calibration masters and some problematic subs to me on the APP server, login/password: appuser
Please create a directory with your name on it and add it there. Thanks!

Posted by: @testclaim5250

I have four sets of images to process.  The first three went very well.  No issues.  Using, what I believe are the same settings, this last set is very grainy and all the stars have halos.  Looks terrible.  Am I missing a setting somewhere.  I have gone through it three or four times, thing I hit something I shouldn't have but nothing is jumping out at me.  

this integration is 59 3 minute subs of the pelican.  Taken with 80mm stellarvue scope and ASI 294mc Pro.

I have attached a jpg of what I'm seeing immediately after integration.

 

Thanks

Eric

 

Hi Eric @testclaim5250 & @vincent-mod,

That looks very odd... it would be very helpfull if Vincent and me could have a look at this dataset.

Without looking, my biggest suspicion would be that there is something happening with your star shapes, diffractions and the use of Winsor Sigma Clipping. Winsor Clipping is known for artefacts around star borders, and it seems this is happening here, only very extreme.... it looks really odd.

Eric, can you upload the data to our server?

https://ariesprodstor.astropixelprocessor.com:7001/

username and password are: appuser

Create a directory with your name and we will have a look as soon as possible 😉

Kind regards,

Mabula

@mabula-admin

My sincere apologies for the very late reply.   You mentioned the winsor sigma clip.  That is exactly what I selected.  I went back and processed again but this time did the straight sigma clip and it turned out fine.  I'm not not to include all the source, that was going to be a massive upload and I had no easy place to put it.  I have attached the new image after selecting sigma clip.

Hi @testclaim5250,

Okay, then winsor clipping is the reason. Winsor clipping is well known for producing artefacts at star borders.

Your result was rather extreme though.. how many frames did you integrate?

You could still use winsor clipping, but then please enable the diffraction protection 😉 that will preserve the good data and the stars.

If you have 20 frames, set the diffraction protection at 4

If you have 100 frames, setting it at 5 would be okay normally.

Kind regards,

Mabula

Thank you for the suggestion.  I had 129 frames on this one.  I will process again with your suggestions.

Thanks

Eric