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KINOKS
08-27-2012, 08:24 AM
I am under the impression that some effects/tools use Y'CbCr and others RGB to manipulate colour. And those that use Y'CbCr have a less of an impact
on luma when pushing stuff around. Which sounds logical to me because in a component signal chroma and luma aren't so tied together as they are in RGB.
Im just doing a short paper on color grading that is due in a couple of days. Can anybody help me with this?

I don't know if I'm just imagining things but when I use curves in Avid the waveform meter doesn't move as much as when I use curves in After Effects.
After Effects work only in RGB space, converting component to RGB.
And I heard in one DaVinci Resolve workshop someone saying that some tools use Y'CbCr and others RGB...

Anybody?

Thx!

Br
S

KINOKS
08-30-2012, 01:40 AM
Anybody??

Jordan Scott Price
09-13-2012, 06:06 AM
Probably a little late to help you with your paper, but...


Yes, some softwares' tools use YUV (YCbCr) instead of RGB. The 3-way Color Corrector in FCP is YUV, but the curves in Color or After Effects use RGB. I, too, find the innate Curves effect of After Effects to be way too aggressive compared to, say, the curves in Color's or DaVinci's interface. The built-in plugin in After Effects called SA Color Finesse (which Adobe bought from Synthetic Aperture) has RGB and HSL tools. HSL behaves like YUV in that luminance (L) is controlled independently of color (Hue - what color, Saturation - how much color). I prefer YUV or HSL tools as I want to adjust my white level, black level, midtones, and luma contrast independently of color.

RGB allows you to adjust all the properties of each color (R, G, B) individually, usually through a curves interface, but even a slight tweak can drastically change your image.

KINOKS
09-21-2012, 10:15 AM
Yes, that's what I thought. Thx for the reply.