I am using the latest Photoshop. When I paint on a new white surface with a brush, everything becomes white as I paint. Also the area around my work surface. So I paint blindly. As soon as I finish the line, the drawing is visible. How can I change that or why is that?
We can see that your image is zoomed to 34% but we don't know the resolution of your display screen. Nore do we know the spec of your hardware. What I am wondering is if this is just lag. You were moving the brush quite fast in the video.
Try using a small fully hard brush (10 pixels for instance) and painting more slowly. If you are still seeing nothiing until the end of the stroke, then we can look more closely. I am not a Mac user and these things are often OS specific, so what version of OSX are you using, and what hardware.