There is no fundamental right or wrong when it comes to line quality in art. In most instances, however, the quality of one type of line may be preferable to another to an artist. Here below in the ink drawing, the lines because they are fine and unblended, tend to be cleaner though not always precise. In a painting such as the one in pastel below, there are actually some blended lines as well as more direct applications of line, but the overall piece is more relaxed in its line quality than an ink drawing. Even with a simple pencil drawing such as in the sketches below, there tends to be combinations of different line qualities rather than just one type. One design book I have read says that the qualities of line are endless, then goes on to give just a few examples such as I have. In truth, there is a lot more to be said about line than whether or not it is precise or relaxed, blended or unblended, delicate or bold, dark or light, straight or curved. The choices as many as there are, can definitely enhance the overall effect in a piece.
I am at the end of the paper samples I purchased, with only the very largest approx. 30" by 40" sheets remaining. This means I have to give more time and thought in the planning for those larger projects. I will still do all my usual sketching and painting, but those larger projects are on the horizon. I hope to share one in the near future, here.
Until next time, thanks for visiting and take care!