I've been having this nagging issue for a while now and I really want to get it resolved. You see, I have the bamboo capture tablet and it's really great and stuff but I really hate how the pressure sensitivity does not replicate, let's say a pencil. When you draw lightly with a pencil, it comes out lightly on the paper. When you draw hard it comes out dark. When I press lightly with my bamboo pen, it just makes the brush size smaller, it does nothing for the opacity of the color. Is there any way to fix this? I've already tried going into the settings, I lowered the "tip feel" to soft and all that did was make it so that the brush size does not change with pressure, which I like a lot because that's never what I wanted it to do. Is this even something that can be fixed? Is it just my tablet that does this, is mine defected? Help please!
If that's the case, then what you're looking for is in the Brush settings panel (you can access it by clicking on the rectangular icon next to the brush size setting in standard interface.
If you want constant brush size, deactivate the "Shape dynamics" option, and as for stroke opacity there's a button next to the brush size setting that displays a check board motive and a pen. Pressing it will activate "pressure for opacity", which seems to be what you're looking for.
You'll probably want to take an extended look at Shape dynamics to learn more about how to configure pressure. There are some cool features you might need later on in here.