[Help] Weird Shadow Problem

[Thedogactslikeacat (Doğaç Bora)]

I tried recalculate normals, remove doubles and use HDR for light too but it didn’t change anything. I think sun lamp is the problem but I don’t know why. Any idea?

P.S. Also walls have default material.

[txusmiCG]

It seems the same as this:

Weird quality on materials after rendering

so after I render my interior scene, the materials are pretty disgusting and overall quality is really bad and I dont get it why this is happening [jhgfgh](upload://5nz247Ctl36I9I3SUGvBb2wdWWg.png) List item

[Thedogactslikeacat (Doğaç Bora)]

Thank you so much! I Don’t know you can see the different but it helps me a lot to understand.