Blurring dark areas

Hi All,
I have a night time shot of two people looking at each other quite strongly lit. In the distance are some faint defocused lights that have to go. I want to just blur them out but in doing so effects the faces to much in the forground. I suddenly had a thought of just blurring the dark areas as this would probably do the trick. is there a goto process that everyone knows that i dont?
Many thanks as always.

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You could pull a luma key for the dark areas that encompasses the faint lights but nothing brighter. Use a comp node to multiply the plate by this. Blur both comp node result and alpha the same and then dived the two blurred results.

Basically the object obliterator on the darks.
Comp back using your luma key.

Matte blur i think it is also called.

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This sounds very promising, thank you i shall give this a try.
It’s one of those jobs which you think should be super easy and is turning into a ball ache.
Thanks again.

Flame Blur Module.

Check the bottom left for a Colorspace tab.

Change from whatever the default is to YUV.

Now there’s a new button that pops up that you can affect luminance, chroma, or both. Pick luminance.

Although, I don’t think this is gonna work the way you want it to.

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Thanks Randy, I didnt know this.

This sounds like a case for K_MaskBlur (or object obliterator). pipe a matte of the BG white and FG black, and blur. The blurring won’t bleed into the FG. Sapphire also has a good tool for this.

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Y_blurs also does the trick. You can input a matte to restrict the pixels that get blurred.


If you have the Sapphire sparks OFX S-blurs has a blur darks option. Maybe with some creative masking this might help you out?

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