1 Reply Latest reply on Jul 28, 2014 11:12 PM by Mylenium

    Set operations using Rotobrush and Masks question

    arakotchian Level 1

      Hi everyone


      I have a relatively simple video clip of an object rotating.  Its shot straight on, no fancy moves or anything just rotating.  I've rotobrushed it and it looks good on a plain white background.  I'm animating a color shift such that as the object rotates its top 1/3rd part changes colors.  The area changing colors has crinkly edges but I've used rotobrush to isolate that as well, no problems there.  I duplicated the original clip, rotobrushed the duplicate to separate it from the background.  The original clip fades into pure white leaving the rotobrushed layer visible.  I duplicated the original again, rotobrushed the top 1/3rd in the same way.  I created a new layer with just a color adjustment effect and used the rotobrushed top 1/3rd as a track-mask for the animated color adjustment layer.


      What I want to do is run a color gradient that shifts colors same as the top part but bleeds into the lower part that does not change colors. 


      So, is it possible to use a regular mask for the gradient and do a difference operation with the rotobrush of the object so the gradient only effects the area below the top 1/3rd which changes color ?  I know I can do it with regular masks, but I can't figure out how to do it with rotobrush masks.  I want to be able to do intersections and unions.


      any pointers would be greatly appreciated.  Thanks