Quote Originally Posted by OldClicker
But if you are in a situation that calls for an ND filter, you are probably beyond the range of the sensor and blowing out the highlights.
TF
This comment and some of the things Greg is talking about make me think that we may be talking about 2 different things. From reading the original post, I was under the impression that the question was in regards to 'solid' ND filters. A filter that would darken the scene evenly across the entire frame allowing for the use of a slower shutter speed. This type of filter would have no affect on the dynamic range of the sensor.

The comment above and Greg's comments about HDR and combining exposures make me think some are talking about split or graduated ND filters.

These are 2 different tools for 2 different jobs, and would make me respond very differently based on what is being asked for.

If we are talking about a solid ND filter, I would say get a good filter and get it right in the camera. If you over expose your image because you want a longer shutter speed, you are going to blow out a lot of your scene. Once it's gone, it's gone. Even if you don't blow it out and are able to get it back, your image quality is going to suffer compared to capturing it correctly in the camera.

If we are talking about a split ND filter, I would suggest bracketing your shots and combine the photos in post to get your final result. From my experience, I can get a much better final image by combining multiple exposures than I can with a graduated ND filter. I can mask in the areas to blend the images together more naturally than I would get with a split ND filter.