Mal, I wanted to respond to your questions. An ND filter is a "Neutral Density" filter. It reduces the light coming through the lens, and is neutral in terms of color. It does not change the color balance. I use a graduated one, which means it's neutral density at the top, and the effect gradually fades to transparent near the middle. It will darken the top half of the photo and allow you to get more exposure on the bottom half, bringing out detail in the shadows of a scene with a huge dynamic range.
Thanks so much. I appreciate all the help I've had from people on here more than you know. I've got some more general questions about filters but I think it'd be going a little off topic so I'm gonna take it over to the Q+A forum. If anyone's feeling helpful, here's the link:
Wow, it's my first day here and I'm beyond amazed! the first shot gave me the chills when it came up. I am really impressed and encouraged how supportive and helpful you all are with one another. I think I'm gonna like it here.
Thanks Jackie I think you'll find that everyone here is willing to help whenever they can. I know I've learned a bunch since joining here, and I'm happy to share my knowledge.