Split Blender Render Outputs with File Output Nodes

Splitting render outputs in Blender allows you to save multiple render passes, masks, or composite branches into separate image files or formats simultaneously. This workflow relies on the Compositor's File Output node, enabling you to organize multi-channel data such as Ambient Occlusion, Depth, or Cryptomattes into dedicated folders without overwriting your primary composite render.

Step 1: Enable Your Required Render Passes

Before setting up the nodes, define which data channels you want to export:

  1. Navigate to the View Layer Properties tab (layered icon) in the Properties panel.
  2. Under the Passes section, check the boxes for the data passes you need (e.g., Z/Depth, Mist, Diffuse Direct, Glossy Indirect, Cryptomatte).

Step 2: Open the Compositor

  1. Switch to the Compositing workspace in Blender’s top menu.
  2. Check the Use Nodes box at the top of the node editor to display the default Render Layers and Composite nodes.

Step 3: Add and Set Up the File Output Node

  1. Press Shift + A and go to Output > File Output.
  2. Place the File Output node next to your Render Layers node.
  3. In the File Output node's settings (accessible in the node or in the Sidebar by pressing N and navigating to the Node tab):
    • Base Path: Specify the target directory where files should be saved.
    • Format: Choose your preferred default file format (e.g., PNG, OpenEXR, JPEG).

Step 4: Add Sockets for Each Pass

By default, the File Output node has a single input socket named "Image." To split multiple passes:

  1. Select the File Output node and open the Sidebar (N key).
  2. Go to the Node tab and look for the Properties / File Slots section.
  3. Click the Add Input (or +) button to create additional sockets for each pass.
  4. Rename each slot to reflect the pass name (e.g., "Depth", "Shadow", "Normal").
  5. (Optional) Expand the individual slot settings to override the base file format or set sub-paths (e.g., depth/render_ will save the pass into a dedicated subfolder named "depth").

Step 5: Connect the Passes

  1. Drag connections from the output sockets on the Render Layers node to the matching input slots on the File Output node.
    • Example: Connect Depth output to the Depth slot on the File Output node.
    • Example: Connect Denoised Image to the main Image slot.
  2. If you are using additional composite nodes (such as color grading or blur), you can route processed node branches into individual File Output slots as well.

Step 6: Render

  1. Press F12 to render a single frame or Ctrl + F12 to render an animation.
  2. Blender will automatically write each connected input from the File Output node to its own file upon completion of each frame. Note that the standard "Render > Save As" command only saves the default Composite node output; the File Output node handles its own file writing automatically in the background.