Channel mattes

[Joseph Owens]

The color mixer is of no use to you?

jPo

You mean “Old Ben”? Ben Kenobi?

[Stig Olsen]

I cant find a way (with that tool) to separate the red from the red channel and so on. When I set lets say the values in the blue/green channels to 0. I still not have a separated red channel.
My goal is to have three nodes with each of them representing each channel in the original image. And then I want those nodes to give me a matte. Any idea?
The reason I want this is to make it ready for the 3-strip process.

Stig

[Chris Hall]

I’m not sure if this is what you want, but I use a technique using a layer mixer in “add” composite mode. Basically make three nodes going into it and in each layer use the channel mixer to isolate just the red, green, and/or blue channels (lower the other channels to zero in that layer keeping only the channel at 100 that you want to control). The result should be individual control over each RGB channel via those nodes. Make sense? (the key here is the “add” blend layer, which literally adds the RGB channels together)

Chris Hall
Colorist – Basher Films
Pasadena, CA

[Charlie Edison]

Yes you can.

In the browse page you can add any clip as matte to another clip, it doesn’t have to be a matte shape.
Resolve takes RGB mattes (or images) so for example (and do this with color bars so you can easily see the effect,
but add an RGB color bars clip to the target clip in the browse page. In the color page add a node and then select ext matte. The clip you added as matte will appear and you can choose which channel to join to that node, then you can grade using the values of the matte channel in your node.

I tried this with two H264 clips which also worked. Resolve internally converts to YRGB processing, so YUV clips work as mattes as well.

hope that helps.

adding a matte: in the browse page first select the clip you want to add a matte too, once selected then go back up to the media browse window (or clip details window) and right click on your clip you want to use as a matte and “select add as matte”
In the media pool you will see a little green square on the far left showing it has a matte associated with the clip, you can double click the green square clip to see the linked matte clip.

[Joseph Owens]

I think the poster wants to pull apart the Red, Green, and Blue content of the original source media, not necessarily add a matte.

This was a node in the COLORFX window in COLOR so that an operator can perform independent operations on individual color channels (like selective noise reduction or chroma blurring to “improve” matte separations), and it also exists as an elective process in most FX compositing tools.

jPo

You mean “Old Ben”? Ben Kenobi?

[James Meenan]

Hey Stig

Any luck?

Are you trying to get a base grade for the 3-strip technicolorish modern/digital look?

Does anyone know how to push hues in resolve the way you can in base light with the hue shift to get that primary RGB..rich colorful saturation.. look.. and push out/away some of the secondary colors?

[Stig Olsen]

Thats correct Joseph.

I do not have a solution James, and yes its for the 3-strip process, but its also neccessary for doing other more advanced grades.
For turning secondaries to primaries you can use the 6-vectors and do all the same things as in Baseligh. For the technicolor look use the hue vs hue. Adjust the “new” hues with the hue vs sat.

[Johnathan Throbins]

Did you find a solution to this? I’m thinking about doing it outside resolve but obviously that would be a huge extra step…

[Dmitry Kitsov]

If i understood you correctly and you want to separate RGB channels here is the solution. Download the files into the same location and then use gallery to import the still.
this is a mathematically perfect separation without channel overlaps like that of the film. to change that adjust each of the color mixer s in the corresponding nodes. For example in the red node only adjust inputs for the red output.
Place any effects downstream of each color node and upstream the layer mixer node.
This of course replicates the math of the print film and not of the negative, but is possible with some tweaks.
Hope this helps

https://f1.creativecow.net/4523/dpx-of-a-solution
https://f1.creativecow.net/4522/drx-of-a-solution

[Johnathan Throbins]

Mmmm… these links do not appear to be complete/do anything, and have a … so I can’t parse it myself…?