Ambient Occlusion Artifact while Rendering

I got a weird AO artifact going on in my render.
i dont know, why this happens. manly because i’m new to blender. BUT all the normals are outside. i already did the CTRL+N “method”. all the objects have a material and none are intersecting.
could it be, that they are too close together?

didn’t find anything with search option. also google didnt help. seems, like noone knows how to fix this, or noone encountered this problem before.

i really hope, that you can help me.
i also attached the blend file, so that you can check it out.

PS: somehow i cant scale the picture down.


room.blend (581 KB)

Try adjusting the Error and and Correction values in the Ambient Occlusion panel
Correction = 0.030 and Error = 0.050 gives this.

thank you very much!!!

and just out of curiousity, do you might know, why this is happening as it is?

The errors seem to be where you have a narrow gap between two objects. With the inaccurate approximate AO methos it looks like this gap is too close so it needs some correction. I’m not getting this with the slower more accurate raytracing AO method with the samples increased to remove the grainy appearance.
By the way, I like the method you used to make the chain at the back