When using a wacom intuos 3 under ubuntu 8.10 amd64 (with tablet correctly configured in xorg.conf), the range of pressure (from hard to low) is very limited from soft to medium pressure only, and there are no parameters for adjusting the magnitude of change in the brush effectively.
When using photoshop CS2 under WINE, with no additional configuration, the tablet works and gives me a VASTLY improved pressure range. I can press really hard and it gives me bigger and bigger brush sizes.
I like gimp and think it's way easier to use than photoshop, but drawing art and sketching with the tablet isn't quite there yet, not only this problem, but it's jittery and harder to draw a smooth line than cs2.

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Thanks for taking the time to look at this!