2

I know how to merge individual channel images in photoshop, but I can't seem to find a tutorial or even mention of how to achieve this with video clips. I have satellite footage shot at different wavelengths (R, G, B). I could take single frames and easily make images but I'd love to do a false color video. I guess I could do all of the frames individually but I'm curious, is there a way to do this in Premiere or After Effects? Any suggestions would be helpful.

Improve this question

2 Answers 2

Reset to default
2

I would put all three files on three layers in either Premiere or After Effects, and play with the different blend modes and opacity of each layer until the image looks right. Screen, Add, or Overlay modes will probably be worth trying.

Premiere: https://helpx.adobe.com/premiere-pro/using/blending-modes.html

After Effects: https://helpx.adobe.com/after-effects/using/blending-modes-layer-styles.html

Improve this answer
3
  • If they are the Red Green and Blue channels then Add mode would be correct.
    – stib
    Jul 21, 2021 at 1:59
  • But OP is asking for false color. Adding would give normal color. If he means false color like the “Predator Vision” exposure tool in some cameras and broadcast monitors, he’d also need to posterize, then remap based on Y’, which I think can be done with the “ramp” effect in AE, if I remember correctly. In DaVinci Resolve, there’s a false color effect that’s just drag and drop.
    – Jason Conrad
    Jul 23, 2021 at 7:27
  • Very good point - please add as an answer!
    – tomh
    Jul 23, 2021 at 7:27
1

Just to build on @tomh answer, to get false colour you will first need to get true colour by added the layers in after effects, use the "Add" blend mode as mentioned, which will get you true colour (rough enough without grading).

Not sure this is exact "false color" but it will work near enough for your purpose I think:

You will need to select all 3 layers and pre-compose them.

enter image description here

Then go into Photoshop, create a blank, empty document of the same size as your footage.

At the bottom of the layers panel, create a new Gradient Map adjustment layer.

enter image description here

Select a gradient map that fits your requirements, or create your own. This is what will map light and dark values to colours.

enter image description here

Now you can export the gradient map as an LUT:

enter image description here

Go through the save steps and note where you save the LUT files to. Back in After Effects, you can add the "Lumetri Color" Effect to your pre-comp, open the Effect, then Basic Correction, then on Input LUT click Browse and import the LUT you just created.

enter image description here

enter image description here

Your footage should be gradient mapped to the LUT you created. Hope that helps!

EDIT: couple notes, the .3DL files seem to work best and go for about 60 grid points. Can add LUT's in After FX or Premiere Pro.

Improve this answer

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.