Denoising in Blender
Denoising is a key feature in every Ray Tracing Render Engine these days. It helps to get noise-free images way faster. In this article, I want to show you, how you can use the denoising feature inside of Blender. No matter if you are using Cycles Render, LuxCore Render, or Octane Render.
Latest update August 12, 2021
Denoising in Cycles
Step 1 (Activate the Denoising Data Pass)
You can activate the denoising data pass by activating the Denoising Data Checkbox. You can find the Denoising Data Checkbox in the Properties Panel under View Layer Properties>Passes>Data.
Step 2 (Switch to Compositing Workspace)
In the Compositor you can set, what should happen with the Image aft it is rendered. In this case, you want to denoise the image. Blender already set up a working space for compositing. You can switch to it by clicking on compositing at the top of the Window.
Step 3 (Activate Compositing Nodes)
To activate the Nodes in the Compositor, you need to click on Use Nodes.
Step 4 (Add Denoise Node)
To add the Denoise Node just click on Add and under Filter you can find Denoise. Alternatively, you can press Shift+A (on Windows) or CMD+A (on Mac). After that, drag the Node between the Render Layers and the Composite Node.
Step 5 (Connect the Denoise Node)
Connect the Denoise Node according to the Image. Noisy Image with Image, Denoising Normal with Normal and Denoising Albedo with Albedo.
(The algorithm has simply more information, which makes it possible, to create better results.)
Step 6 (Activate the Denoiser in the Viewport)
To activate the Denoiser in the Viewport, check the Viewport box. You can find the Checkbox in the Properties panel under Render Properties > Sampling > Denoising.
You shouldn’t use this option for denoising the final render because of a high decrease in performance.
To get back to the default Workspace, just click on Layout at the Top of the Window.
Denoising in Cycles with an RTX GPU
Simply Tick the Box Render and Viewport, which you can find in the Properties panel > Render Properties > Sampling > Denoise.
And switch from NLM to OptiX.
Make sure that you don’t use the Denoise Node in the Compositor. Using multiple denoising algorithms simultaneously can cause issues.
Denoising in LuxCore Render
Step 1 (Activate the Denoiser)
Check the Denoise Box, which you can find in the Properties panel > Render Properties.
Make sure that you don’t use the Denoise Node in the Compositor. Using multiple denoising algorithms simultaneously can cause issues.
Step 2 (Set Halt Conditions)
The LuxCore Render Engine, by default, runs forever.
The Denoiser only starts after the Render. Which is the reason you have to define a point at which the rendering process stops.
You can do that by checking the Box Halt Conditions, which you can find in the Properties panel > Render Properties.
By default, it will Use Time, which means the time (in seconds) defines when the Render Stops. You can also change this to Use Samples where the Render runs until a specified amount of samples achieved, like in Cycles Renderer. Alternatively, you can also Use Noise Threshold at which the render stops depending on how noisy the Image is.
Step 3 (Switch to Compositing Workspace)
In the Compositor you can set, what should happen with the Image after it has been rendered. Here, you want to denoise the image. Blender already set up a working space for Compositing, to which you can switch by clicking on Compositing at the top of the Window.
Step 4 (Activate Compositing Nodes)
To activate the Nodes in the Compositor, you need to click on Use Nodes.
Step 5 (Connect the DENOISED Output)
Connect the DENOISED Output of the Render Layers Node with the Image Input of the Composite Node to use the Denoised Image instead of the default Image as your output.
To get back to the default Workspace, just click on Layout at the Top of the Window.
Denoising in Octane Render
Step 1 (Activate the Denoise Beauty Pass)
Check the Beauty Box, which you can find in the Properties panel > View Layer Properties > Passes > Denoiser.
Step 2 (Activate Octane Camera Imager)
Tick the Box Octane Camera Imager (Render Mode) Which you can find if you select a Camera in the Properties panel > Camera Properties.
Note that this setting only relates to the selected camera. If you are using multiple cameras, you have to do this and Step 3 for every camera on which you want to use the Denoiser.
Step 3 (Activate the Denoiser)
Tick the Enable Denoising and Denoise Volume Box which you can find if you select the camera in the Properties panel > Camera Properties > Octane Camera Imager (Render Mode) > Spectral AI Denoiser:.
Step 4 (Switch to Compositing Workspace)
In the Compositor you can set, what should happen with the Image after has been rendered. Here, you want to denoise the image. Blender already set up a working space for Compositing, to which you can switch by clicking on Compositing at the top of the window.
Step 5 (Activate Compositing Nodes)
To activate the Nodes in the Compositor, you need to click on Use Nodes.
Step 6 (Connect DENOISED with Image Input)
Connect the OctDenoiserBeauty Output of the Render Layers Node with the Image Input of the Composite Node.
To get back to the default Workspace, just click on Layout at the Top of the Window.
