Odd Integration result

Hello
So  my integrated MAster light after WBPP is totally weird and looks like i had bad flats. But my registered and calibrated images look really nice. I re did the whole process manually every went well until the integration... see the attached Jpg of the MAster light and the jpg of a sinlge calibrated and registered imgae.
 I do want to check my flats with pixel math. Can someone remind me of the formula to do so ?
Any thought would be greatly appreacited. I was using 180s subexposures, and calibrated with Master dars and bias and flats. I also imaged NGC7331 two night agao and my flats worked perfectly!! 

Comments

  • I do use an OAG so that is part of the dark bump along the bottom.

  • Andrea,

    I am going to place trust in your observation. If there is absolutely no indication of issues in your calibrated-registered frames... (you had better be correct about this!).... then there is really only one more place the problem can lie.

    Please pause and consider this.

    Ok... hopefully you gave it a shot. What follows registration?
    It is Local Normalization. What does LN do? It matches gradients based on a reference. 

    Question... what does you LN reference look like? You did not say.
    If the same (or similar) pattern exists there.. than you have your answer. The problem is the LN reference is bad and you will likely want to get a better one by using interactive means of LN.

    All of this must be true IF your calibrated and registered frames are perfect.

    -the Blockhead
  • Well you caught me I did NOT DO local normalization because i dont understand it very well and need to review  how to do it again BUT i  kind of knew you might ask about that  so....

    I just ran the full WBPP again and  checked off  Local normalization- it actually failed to find a LN reference frame at all . so i need to look to see why that happened and try  WBPP again with the interactive mode
     I will check back in....

    But to for for sure  know if my  calibrated -registered frames are perfect i should try the Pixel math test right?
    L - MD) / MF * mean(MF)
    I just did that and the calibrated light is lovely!  even stretched there is no wierdness...
    So I  am off to watch LN/WBPP videos now in the hope that it is the issue.

    Thanks for the quick response Adam  
  • Any idea which video I should watch for this? I seem to think I saw the iterative LN in a WBPP video? I can't find a current local normalization video...

  • Ugg never min maybe I do have bad flats….. sigh!

  • How about start with the latest workflow video. 
    I demonstrate how LN interactive works compared to automatic. 
    Did you watch the NGC 1491 video series?

    -the Blockhead
  • Thanks Adam, i re-shot my flats which helped. Then it became clear there was actual flux in the image that I captured but decided not to process as it was faint. I  am now in the NGC 1491 series ( and also watching stretch academy)
     thank you for your time helping me trouble shoot this. Andrea

Sign In or Register to comment.