I'm testing out some clear gesso midway through a painting to see if it helps with the drag of the paintbrush
Recently I've been painting large on canvas rather than small on paper, and really notice the difference between the drag of the paintbrush on each substrate.
With paper, as you drag the paintbrush across, it offloads the paint and provides a bit of resistance to guide the brush. Something to "hang on to".
With the smooth canvas I use, you can get a really nice line and finish, but the trade off is that as the layers build up, the brush can slip off-line more easily.
To try and combat this, I tested out a layer of clear gesso half way through the painting. Immediately I could feel the grainy texture of the roughened surface gripping the paintbrush. It wasn't going to slip anywhere! But now I was getting dry brush issues where it was pulling off too much paint.
I wonder if I would get better results if I mix it half and half with another smoother medium?
UPDATE:
What I've realised is that in my first layers of blocking in, I was using a smooth brush to apply the paint. This left little grip for subsequent layers. So, armed with a stiffer brush, and using heavy body paint, I've experimented with doing my first layer or two like this. Subsequently, there's still tooth left on the canvas when it comes to doing the top layers, with the smoother brush and fluid acrylics. No need for the gritty gesso!