Brush Opacity and pressure problem

Hello everyone. My problem is I used to be able to draw lightly with my wacom and the brush would come up very lightly. You know like you do with a pencil. Then when I would put more pressure with the pen, the colors would show up darker. For some reason now the color just comes out all the same opacity no matter what pressure I put with the pen. Does anyone know how to get back whatever settings I used to have, so I can use the wacom like I would a pencil?

thanks in advance

Select the Pen Pressure option for opacity in the Brush Pallet's "Other Dynamics" section.

-phil