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Halo removal in PS

Started by RobertM, Oct 18, 2008, 16:09:57

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RobertM

I'm not sure how you guys remove those bright halos around stars but I thought I'd share my method anyway.  I'm sure someone has a better method or can refine this and if so then please let me know.

Blue (and all other) halo removal in PS :

1) Zoom in till the halo is half the screen.
2) Use the Elliptical Marqee tool to lasso all the halo (you can move it by placing the cursor inside the ring and holding the left mouse button).
3) Layer -> new adjustment layer -> curves -> ok
4) Click on the area just inside the border of the bright star edge (not the halo) to see where it comes on the curves line and put an anchor just a little further up.
5) Place another anchor half way between that and the lower left corner.
6) Drag that anchor down and left or right to reduce the halo.
7) Place further anchors dependant on how it's progressing.
8) If that doesn't immediately got rid of it then you can do the process again with another layer.

Now the bad news ... repeat for each star individually !

Most halos will become invisible by moving the anchor just a little, others will require multiple itterations to reduce their effect.  It is important to note that there must have been no smoothing of the original image as this affects the halos slightly more than the background - makes them almost impossible to remove completely.

Thanks Robert

JohnP

That's great - thks Robert - I will give this ago & let you know how I get on..... Cheers,  John

PS - I'm sure Chris's answer to this post will be 'Image through an ED80'....... :-)

Fay

Thanks Robert, will try that. When I do, I hope there are not too many to do!!
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!