mojave wrote:We are aware of this and it is in our todo list, at the moment this is a limitation, so the background should be rendered as an environment node.
To be more specific: It is not possible to compose colour filters using normal alpha compositing. You would need an alpha channel for each colour channel (i.e. 3 alpha channels) and if the result is saved with pre-multiplied alpha, it's possible to achieve what you want to do. As far as I know, none of the compositing tools allow something like that. Please correct me if I'm wrong here.
In theory there is no difference between theory and practice. In practice there is. - Yogi Berra