6 Replies Latest reply on May 23, 2017 4:02 PM by Kevin-Monahan

    Edge color changes when overlapped but it can be solved using "Alpha add" mode

    Rodan_Shiner Level 1

      Hello. I have a question.


      I have 2 png images in After Effects. Those images are aliased images.Just like this image.

      Those A and B shape is png images. Both images are ok when they are separated.


      but when I move them and they are overlapped, strange thing happens. I painted problematic marginal area of shape B red.

      Those red areas are the place where original colors are changed.  This color change is  really slight, like "R0 G0 B0" to "R1 G1 B1", but it definitely changes. Alpha value is not changed though.



      I don't know why those color change happens. This happens when I set layer mode of shape B to "Normal".

      When I change layer mode of shape B to "Alpha add", this color change won't happen.  It must be related to alpha interpolation of those images.


      I want to know why those color change happens and what is the right way to prevent this color change from happening. I am not sure "Alpha add" mode is the right answer.

      Please help me . Thank you in advance.