FORUMS: list search recent posts

How to achieve the combination of CC Time Blend and Transparency

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Mehdi Rafeie
How to achieve the combination of CC Time Blend and Transparency
on Jun 14, 2017 at 5:27:28 am

Hi guys,

I am working on a scientific project that entails tracking of cells passing through a bifurcation. A couple of years ago, Kalle Kannisto came up with a perfect solution to my problem of indicating the trajectories of particles flowing in a microchannel (please have a look at it here). Now, I need to do the same with the difference that the trajectories of cells/particles are expected to appear translucent so that the more cells follow the same path, the more opaque it should look.

appreciate your help


Return to posts index

Walter Soyka
Re: How to achieve the combination of CC Time Blend and Transparency
on Jun 14, 2017 at 3:12:33 pm

You need to change the order of operations you're doing here. You were doing a time blend, then the difference; now you need to do difference first, then time blend.

First, create the precomp that shows the difference between the movie and the "clean plate" -- that is, a frame with no visible cells. Then, back in your main comp, use Echo with a lower starting intensity and an Add blend operator to let the brightness values accumulate over time.

Here's a quick and dirty example of this, from your previous upload:



Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
@keenlive [twitter]   |   RenderBreak [blog]   |   Profile [LinkedIn]


Return to posts index

Mehdi Rafeie
Re: How to achieve the combination of CC Time Blend and Transparency
on Jun 15, 2017 at 3:16:36 am

Thanks a lot for your reply, Walter. That is indeed what I am looking after. However, I could not achieve the same result. Could you please elaborate further on your solution?

To do the Difference before the Time Blend, I first imported my new video file as well as a frame representing the clean look of the microchannel into a comp. I then set the blend mode of the video layer to Difference and converted these two layers into a pre-comp. Next, I applied the Time Blend effect on the pre-comp by setting the Transfer parameter to Lighten and Accumulation to 100%. Finally, as you instructed, I applied Echo and tried to play around with its variables with no success.

Your help is highly appreciated


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]