Photoshop Opacity Question

[jetpack42]

I have a Wacom Intuos2 tablet, which supposedly has a hundred billion pressure sensitivity levels. Is there a way to set up photoshop so the sensitivity of the pen on the tablet controls the opacity (rather then the size) of the stroke? I know this isnt a painter question, but I am unsure of where to post this, thanks.

[lowpolymatt]

Did you get an answer to this? Im using 7 and CS and you can do it in the brushes window.
choose any old brush, switch off everything on it (shape dynamics etc)
click "other dynamics" then opacity jitter 0% control set to pen pressure....

that way the brush wont resize with pressure, and the opacity will be opacity controlled...this is one of my default 'roughing out' brushes!

Hope that helps Jetpack.

Matt