---
title: "Denoiser in Blender"
canonical: "https://rmanwiki-27.pixar.com/space/RFB27/544639958/Denoiser%20in%20Blender"
format: markdown
---
![Blender_denoiser_VS.gif](media://fbe0f265-8137-4845-9d0f-80faeba1427d)


RenderMan for Blender includes two different denoisers, the RenderMan AI Denoiser from Disney Research (see [Denoiser](https://renderman.atlassian.net/wiki/spaces/REN25/pages/20420808)) and [Nvidia's AI Denoising](https://developer.nvidia.com/optix-denoiser)<span style="color: #000000"> solution. </span>

> ⚠️ Nvidia's AI denoising is not available for macOS.

## Interactive Rendering

<span style="color: #000000">For more information about using the Nvidia denoiser in "it", refer to the "AI Denoise" section in </span><span style="color: #000000">[Image Tool](https://renderman.atlassian.net/wiki/spaces/REN23/pages/19038407)</span><span style="color: #000000">.</span>

For interactive renders (viewport renders, IPR to "it"), you can turn on the denoiser by going to the viewport preferences and selecting one of the denoisers under IPR Denoiser. Optix refers to the Nvidia denoiser.

![viewport_options-2.png](media://0a9097d3-560a-4f26-a908-873df05bb3d7)


<span style="color: #000000">You should see immediate results with. the Nvidia AI denoiser, like below:</span>

![image](media://0687b1e2-6c5b-4ba7-9a5a-a72429eda68a)


<span style="color: #000000">This is the result with the RenderMan AI Denoiser after two passes:</span>

![image](media://82f2afe8-2a3e-4a71-9a3d-05740f0ed17f)


<span style="color: #000000">For the RenderMan AI Denoiser there are some additional controls:</span>

- Cheap First Pass: if checked, the first denoise pass will use a cheaper (slightly faster but lower quality) heuristic. This can be useful if rendering something that is converging very quickly and you want to prioritize getting a denoised result faster.
- Min Samples: the minimum number of average samples per bucket before interactive denoising runs for the first time.
- Interval: the time interval between denoising runs (in seconds).


For preview renders (i.e.: hitting F12 or Render→Render Image), and you're rendering to the the Blender render window, you can select which denoiser you want to use in the Render Properties tab.

![preview_denoiser.png](media://cca2ed41-8a38-4fbf-9689-22b2a0ab656c)



For the Nvidia AI denoiser, you should immediately see the denoised results in the render window.

![preview_render_window.png](media://18fbd482-9431-4ef1-9fe6-2666b574ef15)

For the RenderMan Denoiser, the denoiser will start after the initial render has finished. You should see a message in the render window that denoisnig has started.


![blender_denoising.png](media://ef61b059-7332-4b53-afc9-5cfd62962581)

And here is the final result after denoising (16 sample render).

![blender_post_denoising.png](media://624523f9-544f-43c1-8ee7-466ca096d744)

#### Options

- **Use Color Pass**: when unchecked the beauty pass is denoised by coming both the denoised diffuse and denoise specular passes together. This can provide a slightly better result. However, this can cause issues if your scene is using any Display Filters or Sample Filters. If this is the case for you, check this box.
- **Asymmetry**: Controls the asymmetry value, 0 is best quality, higher values encourage the denoiser to avoid overblurring, leading to weaker denoising.

## Batch Rendering

For more general information about batch render in RenderMan For Blender, see [https://renderman.atlassian.net/wiki/spaces/RFB27/pages/544639612](https://renderman.atlassian.net/wiki/spaces/RFB27/pages/544639612) .

Note, if you are using Blender Batch, and have the Use Blender Compositor option turned on, then the denoiser setting under the Display section in the render properties tab will be honored.

![preview_denoiser.png](media://cca2ed41-8a38-4fbf-9689-22b2a0ab656c)



If you are using RIB batch render style, or have the Use Blender Compositor turned off, you can turn on the denoiser in view layer properties tab. 

> ⚠️ In this batch render workflow only the RenderMan Denoiser can be used. The Nvidia Optix denoiser is not an option


You’ll have to switch to RenderMan Displays (for more detailed information on using AOVs in Blender, [here is the link!](https://renderman.atlassian.net/wiki/display/RFB25/AOVs+in+Blender))


1. Go to the View Layer Properties and click **Switch to RenderMan Displays**
  
2. In the RenderMan Display, select your beauty AOV and turn on **Denoise**
  
3. Set any denoiser parameters and you’re all good to go!