Decompose to color channels

[denzjos]

With Ofnuts plugin 'Decompose to color channels' I got quick a nice effect on a photo that was taken with a blue spotlicht in the back. Could be done with another workflow, but I found this a quick one.
   

[Ofnuts]

You can do the same with Levels/Curves and flattening out the Blue channel.

Things are a bit different if you just reduce the opacity of the Blue layer, the effect isn't the same as dimming the Blue in Levels.

[PixLab]

If it's to remove blue, no plugin needed...
Just un-tick the visibility of the blue channel, or put down the blue curve of the right side  

   

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