Strange blotches on the floor

[KiDam1205]

Dear community,
i realy don't know where the problem could be...1.7 RC8 but it happened with 1.6 too...
Any ideas would be very helpful

[maru]

Do you mean those small dark spots visible to the left and right? Or the dark areas under the benches?
Could you mark in the image the thing you believe is incorrect?

Both of those look like intended results of using some texture maps or ambient occlusion.

[KiDam1205]

no :)
I mean the strange look at the area where the metal of the benches touches the floor.

The dark spots at the left are from the texture (this is a concrete from corona material library)   

[romullus]

It's hard to say without knowing how actual materials or scene were constructed. Could be ambient occlusion, or distance map, or overly agressive denoising, or lack of UHD precision, or something else.

[Ondra]

my guess is at denoising too noisy image - we need more info to solve this

[KiDam1205]

even if the noise limit is set to 2.5?

[JoeVallard]

I had an issue where one wall was producing some really strange results, turns out somehow i had duplicated the wall and it had two walls taking up the same exact space. That's probably not your issue, but worth a look. Just that area in general seems off. The bench legs almost look like they are a glass. Could also try jumping into the render setup and change "Area to Render" to Crop and just render that area.

All the above if you wanna debug it yourself... best bet would be to upload your scene and have them take a peak at it.