The last option is OpenImageDenoise which is fast and gives good results on my pc. SID works on CPU, and my CPU is not the fastest so that could be a reason. A quick try shows me (Robert, New Media Supply) that Optix is faster but shows blurry edges at some places. The next option of Blenders build in denoisers is Optix which is an AI-accelerated denoiserВ based on a paper published by NVIDIA research. This is an old Blender denoiser which is fast, but looks quite bad with all those splotches. The first denoise that comes with Blender is the NLM denoiser. You might wonder what the difference is between this denoiser and the denoisers that comes with Blender. Difference between BlenderвЂ™s internal Denoisers and the Super Image Denoiser (SID)

The last two options for SID are вЂњrefresh SIDвЂќ and вЂњUse Multi Layer EXR.вЂќ The best is to leave вЂњRefresh SIDвЂќ on, and that means that you refresh the node setup instead of adding a new node group after the current one. So if you donвЂ™t have volumetric, you can toggle that off. Next to the quality presets, you can toggle four render passes: Emission, Transmission, Environment, and Volumetrics. The SID type knows three quality presets: Standard, High, and Super. Where SID is suitable for images, the Temporal type is for animations. (Article rewritten by New Media Supply due to SEO and readability purposes) The addon provides two types of denoisers: SID and Temporal.

The Super Image Denoiser Addon for Blender is an addon that will add a node-group in the compositor to denoise the render.

Denoise node blender