1 Reply Latest reply on Feb 29, 2016 6:50 AM by Mylenium

    How to extract a single alpha channel from a image stream that contains multiple alpha channels?

    marcv0

      I have a image stream (300 PSD files), rendert as a multipass render (in Cinema 4D) that contains many object masks.

      I want to use them as alphamasks for the composition of the final scene.

      (This render contains onely the masks, everything else was rendert seperately.)

       

         

           Here some screenshots of frame 100, opened in Photoshop:

      screenshot_01.JPGscreenshot_02.JPG

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

      When i import this sequence in Ae, it automaticly uses onely the first mask as alphamask.

      Is there any way to select the other chanels, like in Photoshop?

       

      (The sequence is pretty big. I got the best and faster result by rendering this in 8k (onely this render with onely the masks), with the C4D standard renderer and normal antialiasing adjustments.

      that solved all problems caused by resolution, but means rendering every mask seperatly would take to much time.)

       

      Usually i have a workarround for this. (Export every pass on its own from the C4D picure viewer after rendering, by recaching for every pass) But in this case this dont works, becaus of the size.

       

       

       

      Im using:

       

      After Effects CC Version 13.5.0.347

      Cinema 4D Studio R14.041        

      Photoshop CC Version 2015.0.0

       

      on Windows 7, 64 bit

       

       

       

      (i hope my english ist understandable)