I have just purchased a new Sigma 10-20mm (77mm) & Sigma 18-200mm (72mm) len.

Due to the size of these lens over the standard Nikor kit lens, I'm up for some new filters. So what should I buy and how much do I need to spend.

My main use is out doors..landscape, People, buildings, action sports. I live on the Sunshine Coast in Qld so their is a bit of beach work.

Your thoughts please.