Help with orange peel

There was a late 18th century qianlong export platter at an auction and I noticed that the "orange peel" effect on the glaze was really only present in those areas that were painted blue. The unpainted areas of the glaze didn't have those "orange peel' holes.
What's that about? Isn't it supposed to be evenly distributed? (I know nothing about this subject)

 

Salt glaze gives what is called an orange peel effect, and when a salt glaze is involved, it does effect the entire surface. If the effect is only present in a single color, then it must be related to that pigment. It's possible that it indicates over firing.

 

To explain in greater detail, it looked as if the spots were on those places where the brush / pen had first touched the surface under the glaze in the small-detail pictures like trees and flowers. The ends of each brush stroke so to speak.
The colored-in, less sharp big areas however did not have the orange peel.
I'm not sure if it was actually even the orange peel effect, but it looked like the surface of an orange, only the spots were smaller and only visible in the right light. The texture didn't feel particularly uneven.

 

Could simply be a heavier application of pigment at the end of a brush stroke.