Digitale lines/folds appear using brush and patch-tool on plain background

[Pepperpille]

Hi!

When I edit photos taken in studio, and the background need some fixup I usually use patch-tool (or brush, or whatever). But sometimes these "folds" or very digital lines appear. I know I can use a brush and paint over them, but then the pixels locks very different from the rest of the background (more smooth, with no texture, since I am painting over it with a digital brush). Also the brush-tool usually gives me the "folds", just in a circle-shape.

My goal is to not have a digital-background, and keep the texture from the photograph.

Does anyone know why this is happening? Or better - how to fix it?

(please se the attached file)

I work on RAW-files, 30mp, 8bit-16-bit. Adobe RGB og Profoto RGB, MAC.  

[Rafael Aviles]

Your attached image seems to be all black.