SANJIESAN CREATOR / Digital painting
Separate brush flow from the darkness of a whole stroke
A brush may become darker while you move slowly even though its colour has not changed. Krita distinguishes stroke opacity from the transparency of separate dabs, with painting mode also affecting the result. Treat those as separate questions when a soft shadow builds up unevenly. Do not assume identically named controls behave the same way in every painting application.
Make one continuous mark and one layered mark
On a spare layer, use a plain colour and a simple brush. Draw one uninterrupted stroke, then another area made from several separate strokes. Keep the brush diameter and working view unchanged. Inspect where the mark accumulates: within a single movement, at a pause, or only after lifting and returning. That distinction is more useful than comparing two random patches painted with different speeds, colours and brush sizes.
Change only the control under discussion
Duplicate the preset before adjusting it. Compare one documented flow or opacity change while keeping the painting mode visible. If a pressure sensor is active, note that relationship rather than treating the slider as the only input. Return to the original sample after each change. A very pale brush can appear improved simply because every mark is harder to see; judge whether it actually makes the intended shadow easier to shape.
Bring the result back to the shadow edge
Try the selected behaviour on a small duplicate of the painting area, such as the soft transition beneath a folded cloth. Check the first pass and a later correction. If the second pass produces an unwanted band, reconsider how the brush accumulates instead of repeatedly blurring the result. Keep the original preset available. The goal is a predictable way to build this particular transition, not a universal best flow setting.