Which Filters

[beaujest4]

Gday people

As the tittle suggest looking at getting myself some filters and was hoping to get some kind words of wisdom from your collective well of knowledge and experience. I have been searching previous posts and found this thread to be interesting and helpfull and part way to answering my question.

http://www.ausphotography.net.au/for...ad.php?t=38885

We currently have a Nikon D300 with an 18-200 and a D40 with the kit lens 18-55 and 55-200 and a 35mm f1.8 While the 18-200 is 72mm dia the other three are 52mm

After talking to our local camera man today it looks like I am getting some Cokin filters. Part of the trade off to buy filters was a Polarizer for the wive's D40 so Circular Polarizer in both 72 and 52. The 52 will be the Standard one and the 72 will be a Pro Series. From there we are getting some drop in ND and GND filters.

We are more into the landscape, seascape nature photography and apart from, I think it was a soft GND8 filter (goes from clear to ND8). my question is, "What other ND or GND or other filter do you people find you can't go without?"

Unfortunately I can't get one of everything and after the other stuff I should be able to get a couple of the other ND filters, so I am asking for your collective expert advise for what to get to start with and to build on as we go. Thanks for your enlighting help and insight into the world of ND and GND filters.