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Noel Carboni Astronomy Tools selectively removing Purple Halos from Stars

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Hi everyone, my first post on here, still finding my feet with PS.


I have the Noel Carboni Astronomy Tools Action Set, I am trying to remove the purple halos around stars in an image of the Large Magellanic Cloud, however when I use the tool it removes a lot of the colour in the nebulosity of the (dwarf) galaxy (I also used Defringe in Lightroom which had the same effect).


I have tried to select the galaxy with the lasso tool and invert the selection and then run the action, however it applies the action to everything regardless. 


I wonder is there a simple way to separate out the galaxy, run the action and then put the galaxy back in? Can it be done using a mask and then blended back in? If so I'm not quite sure how to do this.


Thanks in advance.

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Hi Jon. Welcome to the forum.

If you duplicate your image run the action on that.

Copy and paste the duplicate over the original as a layer.

Then just use your eraser over the part you wish to remain unaffected by the action.



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