Why node Z combine doesnt take into account Glow Blur and Glare? I need to use z combine but i caannot///to use alpha over or MIX node - is not a solution for me because i have a lot of layers and objects and this is animation. So for example lets say i have Earth\ Space elevator\ and glowy objects on it and than spaceship flies around and i can see glow through the spaceship because z combine node takes into account only object itself but not materials ID masks and effects on that object.
Z combine does not work with semitransparent elements.
Very bad. So what will be the solution.
Deep compositing, but it is not supported in Blender and is not for the faint of heart. In Blender unfortunately you have to make do with holdout mattes, render layers and other traditional stuff.
Shit. I think developers should do something to it, it is hard for them to make z combine node to work with semi transparent elements?
^^^Yes, it’s quite challenging. For example imagine dealing with a deep field of semi-transparent leaves or hair, representing potentially thousands of discrete alpha values for each pixel. Rendering is not so bad, but for comp you’d have to code the cool stuff like 3-d masking, depth shadows, and relighting. The example would be compositing an object in depth among the leaves or hair (or volumetric glow). You need a lot of data to decide the alpha at each pixel.
Because of this, the computing times and file sizes grow very quickly. Even the big houses like Weta cheat their deep compositing work with tricks like precommitted shadowing/lighting (ie, they decide beforehand where volumetric lights are so they don’t have to compute shadows dynamically in comp).
OK. Thanks. Good to know