> > I don't see anyplace where curves, levels, contrast, brightness, etc.
> > can be changed.
> I agree that the interface is not intuitive (especially for Mac users)
> but
> Vuescan does have some of the adjustments you are asking for:
>
> On the Color tab, the Black point, White point and Brightness sliders
> give you some control of levels, contrast and brightness -- watch the
> histogram change as you fiddle with them.