In some places an abundance of water caused the pigment to be very light, even lighter than it appears in the photographs. Recently, I learned for a fact (not just by accident like in the painting at right) that using too much water can separate the pigment from the acrylic binder which reduces the paint film integrity and possibly it's ability to permanently adhere to the substrate. So if I feel it is necessary, I may end up brushing a little polymer medium over the surface to strengthen the pigment bond to the paper. (I used a spray varnish on the diamond painting.)
If you like you can read about my first experiments with the water brush and Inktense pencils by clicking here.