QUESTION "Bump"-artefacts at the z-height of top-layers

[glx 23]

Hello :),

 

I noticed some strange artefacts on my prints that affect parts in a z-height where a solid top-layer occurs on another part of the print. I’m not sure whether I’m doing something wrong or it’s some kind of bug. There’s always a bump in features that continue in z-direction through an area where at another point at that height a top-layer is. I attached some pictures below because I’m not sure if you get what I’m trying to describe. I can’t spot these artefacts in the slice-preview, they do not depend on the printer (UM3 or S5), occur regardless what material I use (the pictures are PLA ones, the one printing is ABS). Also the Cura-version doesn’t matter (had this in all versions including the betas I used so far). I’m using the default profiles (Ultimaker PLA respectively Generic ABS with only adjusted temperatures). Also these bumps seems to be smaller the larger the feature is.

I don’t have deeper knowledge of how Cura does things but I could imagine it does something with top-layers but applies it to the entire layer instead of just the part that actually is the top layer.

Does anyone have suggestions what to change to get rid of these bumps?