/ic/ - Artwork/Critique

How doi I set the blur tool (I assume that's the one) in manga studio to give me an effect like this? Which is to say, that little blur/smudging of the lines?
I know the tools are there but they aren't quite right, they require me to put a lot of pressure on the pen for some reason and the blur comes out too large, unlike an actual blurred line as in pic.
I need it to be tighter, if I set Spraying Effect in the options it does become easier to blur but it still is gigantic and totally unlike a straight line, even if I lower the brush size.