Hello ahmetturan,
This seems like a complex issue that no one has responded too, therefore at this point I would recommend contacting the Support Department.
Xerox 4595 scanners image quality gone bad after initializing nvm values. It wasn't my first time of initializing nvm values, i did it once when i had problem with drum unit and at that time i didn't have such problem with scanner, but this time image looks awful. i'm not sure about the relationship between this problem and nvm values this problem may already accured before maybe i realised it after that. copy results are same as scanning results so i'm only sending scanned documents.
What i did:
Scanned documents: https://drive.google.com/open?id=183sEc2Zdb_q7VV7H3sZR74rwjIVuSaPW
P. S. All of these are scanned from flatbed. "R" means short edge first at A4. "scanner_test_shapes" printed and scanned at A3 size. Paper is standart Navigator 80gsm.
Thank you :)
Edit: Minor spelling mistakes.