yellow ‘stains’ on face

[Darby Edelen]

[jochem] “can I do something about it?
some sort of channel blur? (but there’s no yellow channel!)”

Well, if you look at your 3 color channels (opt-1 through opt-3, or alt on a PC) you’ll probably notice some blotchiness in the Green channel (I’m guessing). Skin tones are mostly Red with some Green and little Blue. Yellow is a combination of Red & Green, so I would guess that in those blotchy areas you have Green levels that are higher than you’d like.

I can think of all sorts of creative ways to try and minimize this. You might be satisfied with a Channel Blur but I wouldn’t be =O

You could, for example, try creating a matte from your Green channel and, using this matte to limit the effect, reduce the Green Levels only in the blotchy areas.

Darby Edelen
DVD Menu Artist
Left Coast Digital
Aptos, CA

[Darby Edelen]

I looked at your posted jpeg in AE and it looks like it’s actually blotchiness in the Blue channel (the Blue levels are lower in the yellow areas) that’s causing this.

Darby Edelen
DVD Menu Artist
Left Coast Digital
Aptos, CA

[Darby Edelen]

Here’s a rough fix I attempted making adjustments to both the Green & Blue channels.

I evened out the Blue channel by increasing the levels in the darker areas and evened out the Green Channel by decreasing the levels in the brighter areas.

It’s not perfect, but it should give you an idea of what can be accomplished using mattes from the source’s channels and adjustment layers.

Darby Edelen
DVD Menu Artist
Left Coast Digital
Aptos, CA

[Johan Hoogendoorn]

hey, that’s terrific
I’m gonna try it as soon as possible (it’s already quite late now in Holland, around 11.00 pm)
jochem

[Johan Hoogendoorn]

hmm, Darby, I’m afraid I’m not getting it yet

I duplicated the layer of the singer and set a ‘set matte’ effect on it
https://www.flickr.com/photo_zoom.gne?id=1439198053&size=o
the blue channel indeed looks horrible! the singer now does too

but guess this is not the way?

in other words: how do I transform the blue channel to a matte?

jochem

[Darby Edelen]

Here’s a faster solution, which worked beautifully on your sample section of skin, but will probably wreak havoc with colors in the other parts of your footage.

You’ll still need to create a decent matte of the skin, but then try using the Color Correction>Channel Mixer effect and changing the Blue-Green property to 75 and the Blue property to 25.

I can’t really give you advice as to how to pull a matte for the skin without knowing what else is in your footage.

Darby Edelen
DVD Menu Artist
Left Coast Digital
Aptos, CA

[Johan Hoogendoorn]

Hi Darby,

appreciate your help!

the singers face is ‘encapsulated’ in a sort of flying pane/layer
like this: https://www.flickr.com/photo_zoom.gne?id=1451280359&size=o
(that’s not his actual face, but I’m not at home now)

so there will be not much interference with other elements of the composite
maybe I draw a mask around the eye..

I will try the channel blur-tip asap

but.. I’m still so curious (will be useful for cases in the future) about working out your previous tip:
how to extract the blue channel and convert it into an (adjustment?) layer, aplly levels to it..

regards,

jochem