Render Layers

A couple of weeks ago we were introduced to render layers and how they would be used. Render layers allow for more control in post production, as there are normally many different pieces brought together in vfx it's good to have this control as things may not match up perfectly with one another and will require adjustments. They work in a similar way to how the layers do in maya, by putting different objects on different layers it allows you to render out those specific items. When it comes to render layers, you typically would render out a colour pass, shadow pass, reflection pass and an ambient occlusion pass. On each new render layer you create you can apply overrides onto them which will just affect that specific layer. One of the main uses for overrides is the naming system, another one would be for an object to receive shadows but not emit any.

For my scenes I will only be doing an ambient occlusion pass as this will help the rendered shots sit better in the scene. Ambient occlusion is self shadowing and just gives it that extra bit of depth and realism. I thought of maybe doing the other passes but I didn't think it would be that necessary, any adjustments to colour I could easily do within After Effects itself, the reflections are all set up to how it should be within Maya anyway and as for shadows there aren't that many due to the floor being black. For a scene that was more realistic I can see how these passes would be really beneficial, it all adds to that realism and helps the overall composition. As you can see below this is one of my frames as an ambient occlusion, it gets rendered out with an alpha channel so that the background will be transparent (this is just a screenshot so the transparency is replaced with grey). You can see the shadows on certain parts of the alien and the tree and once put together with the final comp, it really helps the alien shot sit better within the scene.