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Ran into all sorts of issues with this and couldn't quite get the colours right. Star masks were nigh on impossible so I skipped deconvolution altogether. There is a lot of data in this (2 panel mosaic, 10 hrs in each HA, O3 and S2 for each panel) but I feel that the HA wasn't as sharp as it could have been. It may still have something but I'd be interested in other's opinions please? Thanks for looking,

Steve

 

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Ran into all sorts of issues with this and couldn't quite get the colours right. Star masks were nigh on impossible so I skipped deconvolution altogether. There is a lot of data in this (2 panel mosai

Here you go. I've re tried MT and it does produce the artifacts. 

I have completely re-processed the image now and this is the result.   Hi-res here  

Posted Images

To me it looks overprocessed and it's very easy to see the "vaseline" look from way too strong noise reduction, it's actually so bad there's "filaments" appearing all over the image that shouldn't be there.
I think you should start over try to use less processing steps, it should end up looking a lot better and more natural :)
Also remember that a lot of noise you can see at 100% resolution will be removed when you downsample an image. 

I'm sorry for the harsh comment, but in my opinion it's better to be a little harsh and help with constructive critisism than leave the standard unhelpfull "that's perfect/that's awesome" type of comments.

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Thanks xplode but I’m afraid you’re way off. Noise reduction was very minimal through MLT - the amount of data helps here. The filaments you refer too are a by product of morphological transformation to reduce the stars and this was caused by my inability to produce a star mask of any value. I’ve been reprocessing this all day and I’m not sure whether my initial DBE is causing issues right at the start or not but there is something in my steps that isn’t working. Have a look at Sara’s version on her web site, her colours are far better. 

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I may by off about the cause of the filaments, but if you run a process that creates artifacts like that you should step back. You will usually see the same kind of filaments on images with lots of stars and heavy noise reduction.

At the resolution your image is uploaded at most stars will look tiny anyway so there is no need to reduce the star size.
Sarah's image is really beautifull and has very nice processing, i don't think you would be far off with your data if you can take a step back with the processing.
Her colors are different so there's definitely something that can be done to your color calibration.

I've found that with good enough flats there's usually no need for DBE, could your flats be creating issues by leaving small gradients?

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It could be, I wasn’t overly happy with any of the masters to be honest. I have a very dark garden too but some of this was shot under strong moonlight so it could be the data. I’ll revisit tomorrow. 

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1 minute ago, steviemac500 said:

Sorry, artefacts on which image?

second.

image.png.9a43c87cf7f17f4ce3491e29fed6a941.png

I know it is tiny stars, but I think they might become too small. That's why I would like to see how big they are before you morph.

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Yes, you’re absolutely right, they are without doubt a by product of processing. So the MT happens very late in the processing, in fact it’s usually the last thing I do.  The final image is the result of only 1 iteration with MT with .20 amount and 0.75 selection. To my eye, it was the best compromise as any higher settings increased the artefacts a lot. 

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23 minutes ago, Datalord said:

second.

image.png.9a43c87cf7f17f4ce3491e29fed6a941.png

I know it is tiny stars, but I think they might become too small. That's why I would like to see how big they are before you morph.

It is quite bad when you pixel peep 🙄. I’ll have to have a look at the data later as it’s on the on the other computer. I may just forgo MT altogether. 

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46 minutes ago, Xplode said:

That looks a lot better 👍

Totally agree. Keep the stars. They are small and pinpoint and part of the picture. The alternative is to make a completely starless version, but I don't know how to help you with that.

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8 hours ago, carastro said:

The final version, (without the noise reduction), looks great.

Carole 

Thanks for the support guys, the learning curve as ever remains high. @Xplode, sometimes you need a shove to refocus and quit bad habits, I may lay off MT for a while 😉. @Datalord, thanks for your help and finally @carastro, just to be clear, it was the Morphology causing the artifacts not the noise reduction, in case anyone else was wondering. 😂😂😂 

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56 minutes ago, steviemac500 said:

You better hide @ollypenrice  

But then again you all seem to like Sara's rendition (quite rightly...)

Still, if you like trying to mend your watch while wearing boxing gloves you'll love PI!

:Dlly

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