Enhance a picture with compositing

Now that we have a raw render, it is time to learn how to improve it using the compositing tools of Blender.

Introduction to nodal compositing

Blender is a complete tool that also allows compositing. This is the ability to edit an image or a sequence after the rendering phase. You probably have already tried compositing, maybe unknowingly. For example, Adobe Photoshop© is a software that allows us to composite a single image. Unlike Adobe Photoshop©, Blender uses a nodal system that provides a great flexibility. We can make changes at any point without the loss of information. Let's try this:

1. For a first approach of nodal compositing, let's open a new Blender scene.

2. In order to access the compositing mode, you must open the Node Editor. This is the same as the Node Editor for materials.

3. We must then check the Compositing button near the Shader button in the Header options. It is a small icon button symbolizing an image over another.

4. We must also check the Use...