im asking this, because of my make-a-bevel-by-hand project

what is the difference between feathering and blurring ?

does feathering give more control than blurring ?

are you talking of selections ?

If so feather selection is = to apply on the selection channel (or to the quickmask ) the same amount of blur (i.e.feather selection of 5 is identical to apply 5 of gaussian blur to the selection channel )


No, the contrary if you feather a selection you can't see the result because the selection display with marching ants can't visualize partially selected pixel (and "feathered" here is = to partially selected )

If you apply blur on the selection channel or on the quickmask you may instead see well how much the blur modify

Anyway it is true that you may check the effect also of "feather" once done by simply clicking the display quickmask button,
but i prefer blur directly the quickmask

@Esper:
And don't forget the blur tool (really fuzzy brush + opacity required) !
It seems I've decided to play the you-can-also-do-it-manually role in your by-hand quest (:

There is a very small difference in the result(*) but I doubt it's important. Feathering is faster, blurring gives more control (different X/Y value, or other blur methods (spread noise...)).

(*) bucket fill both selections on different layers, put in difference mode, new from visible, and see histogram

thanks for all the comments !

Feather applies a gaussian blur on the selection channel. If you then use the selection as a layer mask or something, only the alpha channel will be blurred.

When you apply gaussian blur on a layer, it blurs the alpha, and also all the colour channels.

So if your layer is monochrome, there is absolutely no difference. Note however, that when you create a new transparent layer, it actually creates a black layer which has an alpha value of 0. So if you then draw white text (or something) on that transparent layer and then use gaussian blur on it, the white of the text (or something) will be mixed (blurred) with the black, giving a sort of gradient to the blur. So in this case, the result will be different if you use gaussian blur or feather.

wow dd !

how comes you know all of this ?

Trial and error, mostly. I'm a very curious person.