film scanning really is a complex art in itself, and i've learned that the hard way. after much experimentation with different programs (Silverfast, Vuescan, and Epsonscan) i've found that while Vuescan gave me the best film negative scans, Epsonscan proved much better for slides. the grain seemed sharper and the color was much more accurate. here are comparisons:
Vuescan
vs Epsonscan