Sometimes a scene will have a wider exposure range that what can be captured, and digital has less range that film. The recommendation for film is usually to lean towards overexposure. With digital, the opposite is true. It's easy to blow out the highlights (make them pure white), and once that happens, there's no info there to recover them.
My suggestion would be to expose for the bright areas, and then hope you can pull shadow detail out in software. My preference is also to shoot in color and then convert in PS. This gives you a lot more control.
Do you have an example to post, both before and after you processed? We might be able to make suggestions based on that.