Too much noise when I play with saturation

[Filip Vandueren]

Using a simple desaturate on especially DV footage often gives you terrible noise:
it factors in too much of the Colour information which is poorly sampled in those codecs.

Two solutions:

A better quality greyscale is achieved by first blurring the colours before desaturating:
either you precompose the video, duplicate your video layer, blur the top duplicate and set it’s mode to Color
or
You Blur your video layer and add a CC Composite set to Luminosity.

However,
The highest quality Greyscale is achieved using a Channel Combiner:

From: Luminance To: Lightness only

or:

From: Luminance To: Lightness
then do your Hue/Saturation and levels

with this, Desaturating seems to get the same result as Lightness Only, and you can selectively desaturate just your yellows.

The Downside is that you get a different greyscale result then if you’d just desaturate, But one that is often more logical and contrasting in my opininon.

a comparison:

DV CODEC RGB:

Desaturated with Hue/Saturation:

Desaturated with Channel Combiner;

Notice how bot the Cyans and the Lime green Turn out lighter with this method.

[Jason Rouleau]

Terrific post! very informative!

I didn’t try using the channel combiner, BUT, I did take your advice on duplicating the layer and setting its mode to Color then desaturate the dup layer and it worked like a charm! No more noise

[Chris Smith]

Also, it’s bad form to ever BOOST saturation despite what format you’re working with. If you want to naturally increase saturation than use the levels to add more contrast to the image and the saturation will boost on it’s own. Often times you need to pull it back a bit. Also to get rid of the yellows, you don’t want to jump to secondaries right away like you’re doing (which is grabbing a color and trying to change it).

Use curves and drop the gamma in the red and green channel a bit to neutralize the yellows. So over all the image is balancing out. When you grab just one color and tweak it, you inherently get very unnatural looking results and should only be used to bump a color a little bit here and there. Where most color correcting should be done by swinging the blacks (shadows), gammas (mids), and Whites (highlights).

[Jason Rouleau]

Very well said.

Unfortunately the scene I am working with was a complete nightmare. Camera B was 2 stops below Camera A, they both weren’t properly white balanced and the lighting changes in pretty much every scene. Up to now I’ve managed to make everything look good, its just that its all a bit noisy cause I’ve had to play with the saturations alot just to get the right look I was looking for.

I tried playing with curves a bit, but still the noise remains… no biggie though, the rest of the movie seems to be fine. Its just this one scene that needed ALOT of attention