I am trying to bring up the specular highlights of a CGI porcelain object, in the compositor, to give the illusion of direct sunlight. I have taken the “glossy-direct” output from “render layers”, and fed it into an RGB slider—darkening everything except the brightest highlights. The RGB output is then fed into the bottom socket of a mix node, with the “image” output from “render layers” in the top socket. A viewer node shows me the mixer output.
However, when I apply “screen” in the mix node, the image actually darkens. Plus, the contrast shoots through the roof. On top of that, the brightest areas of the highlights, now turn black. I get much the same result, if I try to use “add”.
One thought: could it be trying to display in HDR mode?