Thanks! Yes, images are quickly overexposed. ND-filters are great tool for this. Though, it can be a bit difficult to find the right ND-filter for the image you want to create if you haven't used ND-filters before, but that is the fun thing about photography: it won't harm anybody if you just keep on trying. You are already taking great pictures, so I am sure you will master the use of ND-filters soon :)