This link below shows how to get value of RGB color and z-depth from viewer node, that corresponding to the value on the pixel information bar (figure below).
Link : How to get Color and Z-Depth from Viewer Node?
Question is, how do I get the value of the Luminance of every pixel from the rendered image that is corresponding to the luminance value on the pixel information bar? Can I get the luminance value from the viewer node too, same method like the link? Do I need to use additional nodes to get that value?
