Is the floor reflective? Is this an interior scene lit through windows? Those are difficult scenarios to render. Your settings work in most scenes, but they break in a difficult lighting case like this one.
First, make sure you aren’t using an animated seed (in the advanced tab). This is something that people sometimes tell you to do, but it’s really only good if you aren’t using the denoiser.
Now, let’s talk about the sampling settings
The problem is likely the lack of a “min samples” value. If you leave that number at 0, Cycles will pick a value for you based on the “max samples” and the value it will pick might not be adapted to your scene. For a case like this, you might easily need 128 min samples or more.
Meanwhile, your noise treshold of 0.002 is so low (high in quality) that it probably does almost nothing. You probably reach the max samples before the treshold has had the chance to do much, making the render take longer than needed. You could try to set it to 0.01, as your quality is most likely being bottlenecked by the 2 other settings anyway.
Here is a thread where I explain what the sampling settings do if you are interested.
Is there an HDRI or sky background coming through windows? Make sure you are using light portals in the windows. It won’t help with the direct sunlight, but the diffuse sky light coming from every direction will be a lot cleaner.
Also, make sure your windows have their shadows disabled or use a glass material with the shadow disabling trick.
Having a scene lit mostly by sharp beams of sunlight on a floor is a really noisy thing to render. Raytracing renderers like Cycles have a hard time finding those narrow patches of light on the floor.
I don’t know if your skills are at that level yet, but if I had to render an interior scene, I would bake the indirect light of the walls and ceilings to textures. This massively accelerates a render, because it makes the bouncing light cleaner across the whole scene.
Here is an example and explanation, if you have the knowledge to follow.
Something else that can help with this problem is the double resolution render trick.
- Set your output resolution to 200%
- Reduce the sampling quality until it takes the same amount of time to render as before. You will get the same amount of rendering effort but spread over more pixels.
- Denoise and export the images at that doubled size. The denoiser will have more data to work with thanks to that extra size.
- In an external software, reduce the images back to their intended size. last time I checked, Blender’s sequencer wasn’t the best at this (bad filtering), but it’s been a while since I checked.
This also has the benefit of better conserving texture detail through the denoising process.