Chris,
With neutral density filters, you don't need HDR. HDR is garish and the software tries to decide what pixel to put where, rather than you having complete control with a filter, and exposing correctly for the foreground.
Holding the filter over the lens allows you to dither it a little bit, which avoids the harsh gradients often seen in photographs taken utilising a neutral density filter, popped into a filter holder.
H
|