Displacement map trouble

[Kevin Camp]

since you have the guy roto’ed out, you might be able to use a time effect, like echo, cc wide time, or cc time blend, which will all composite neighboring frames on top of the current frame to create motion trail like effects.

you could then try using that effected layer (in a precomp) as a displacement map on the original footage for the air rippling effect. you might also be able to use the precomp on top of the footage with a blending mode like add or screen to create the color streak effect on the shot.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Shane Benson]

If i were to use any of the time effects, like echo, etc, would the trails be able to stay in place as the camera moves? My footage has quite a bit of camera movement, (panning and rotating) so the trails would have to stick, (hence why I tracked the shot and attached the roto’d trail frames to nulls)

nothing as of how has been precomped. The timeline has 50 roto’d trail layers, and then the original footage beneath it.

[David Bogie]

Displacing the air or adding to the distortion like a heat haze?
Displacement mapping only moves pixels around based on the luma value of a source layer.
I love what you’ve got now so, if you want suggestinos from the wonks, you’ll need to explain clearly what you want to improve in the scene and you might want to tell us why you think it needs improving.

bogiesan

[Shane Benson]

First of all, the video I posted above is not mine. Its just showing the effect that I want to recreate from my own footage. I should have made myself clear on that one. Sorry.

Here is my footage that im currently working with.

Kenny_roto_test from Shane Benson on Vimeo.

You can see the roto’d frames ive made that come off of his body as he runs. What im trying to do is get those roto’d frames to act like silhouettes that displace the air as shown in the first video I posted.

The problem is that I think I need to change those roto’d frames into white mattes, then somehow find a way to outline them and then use them to displace. But the process of doing this is what im not familiar with.

[Kevin Camp]

since you already have the motion trail created, you won’t need the time effects.

what you will need to use the motion trail as a displacement map is to have it as a single layer… so if the current motion trial is made of many separate layers, or from an effect (like the time effects), you will want to precompose all those layers into one precomp… just select all the motion trail layers and choose layer>pre-compose and choose to move all attributes.

now you can add the displacement map effect to the background footage using the precomp as the displacement map (hide the map) and you should start getting some distortion to the background footage as the motion trail moves on. you may need to blur or further effect the motion trail comp, to do so, you’ll need to do the effects in the precomp, not on the precomp… e.g. if you want to blur it, you can’t add the blur effect to the motion trial precomp, it will need to be added to the layers that make the motion trail inside the precomp.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Shane Benson]

Ok, I think im understanding it better now. It was the steps I was getting confused. At first, I was trying to use the D-map without any pre-composing.

Those motion trails also have to fade out and slowly scale up in size, so im fairly sure that will need to be done before the 50 layer are pre-composed, then they have be used as a D-map.

Thanks for the help.