Post processing removal of Vignetting etc

Hi Greg, 

To correct your integration/stack with the vignetting correction tool:

• use the third model, elliptical Kang Weiss with geometric factor. This is the most complex model and should give you the best correction.
• place the boxes over areas with only sky background and stars. Lots of stars in the boxes are no problem. And spread the boxes evenly.
• the required number of area select boxes is a minimum to get a good and stable model. So try to use more boxes and spread them evenly over the entire image. Don't worry if boxes turn yellow. If boxes turn red, remove them or double check that they are placed over an area with only sky background and stars. 
• The yellow and red boxes don't necessarily mean these boxes are bad, but they indicate that they could be bad, so you can double check. If you are unsure, remove them and try to find another spot.
• finally, if you can't get a good correction, due to too little area's with only sky background and stars, try to get a better correction with the "remove light pollution" (gradient) tool. That can sometimes give a better result.

Let me know if this helps 😉

Mabula

OK. Thanks. should the image look like an image when i'm done? It seems like the finished image is lost in flat-like whiteness, then I hit OK and am left with no image. Ill give it another go here before I whine again.

Hi Greg,

Yes, after having pushed calculate, the model is calculated and applied to your image. The correction is shown on the screen. If you push Ok,  then it will be saved like shown on the screen.

"It seems like the finished image is lost in flat-like whiteness, then I hit OK and am left with no image"

Okay, I think this happens due to an unstable solution. Try increasing the number of boxes to get a stable and better solution.

Possibly share the image with me so I can have a look? Or post a screenshot of it?

Cheers,

Mabula

OK, I processed as you suggested, and did get a final image this time. It's hard to tell if progress is being made when the step by step results look so bizarre and destructive. Hopefully in time I'll get a feel for whether things are going right or not, as this took only 4 iterations of box selecting and applying. It had been taking me dozens of iterations before I knew the technique better, and I would end up with rubbish. This is promising at least, thanks. I took screen shots of the 5 steps i acquiring the V corrected image:

OK, I processed as you suggested, and did get a final image this time. It's hard to tell if progress is being made when the step by step results look so bizarre and destructive. Hopefully in time I'll get a feel for whether things are going right or not, as this took only 4 iterations of box selecting and applying. It had been taking me dozens of iterations before I knew the technique better, and I would end up with rubbish. This is promising at least, thanks. I took screen shots of the 5 steps i acquiring the V corrected image:

This is a Dropbox link as the upload here seems small.  I think this forum has a problem with the link?

Dropbox File (Private or Invalid)

Hi Greg,

The first result really looks odd, could you possibly send me the integration fits file that you are trying to correct. Look like it triggers a problem.

In the steps, don't worry about boxes being yellow or even red, it just means you need to double check that you have placed these boxes over areas with only sky background and stars 😉

I am preparing a video tutorial showing how I use the tool ( and the remove light pollution tool as well)

Mabula

I'm in trial mode.  So far (though it's confusing) I've not read a manual) I did the  1-2-3-4-5 tabs and left defaults. I have no darks or flats as I usually don't like using them. (simplicity).  So I made a integrated image. (I can't drag and drop from my data files? but I double click the "integrated file" in the list at the bottom. It appears and of course (no flats) has some heavy vignetting.  I often would use photoshop and select the area and bump up levels to eliminate it.  I created boxes (several times) and never got proper results). often inverted vignetting with white outer area instead of black.   I DO LIKE that the stacking was easy.  I've been using pixinsight and we'll it doesn't like my  "quick and easy" methods (often not complying to my requests if I don't have calibration frames).  so I'm looking for something more automated. 

Though I like it in the hour I've spent with it - I haven't fround a good manual yet. I found 2 online and searched for "vignetting" and found one such bit in the guides which didn't really talk about the vignetting correction TAB under tools?    I'd like  a manual that I can seach for a tool and read how to use that tool.  So many manuals are HUGELY over wordy and get into things that I have no interest in reading about. SHOWS promise - but I think I have to maybe go look for youtube  "STEP BY STEP" videos. 
logically pecking around can only get me so far. 

I also thought it would debayer (I checked options on) and it didn't... so again I need some guidance.