I was thinking of getting a cheap 10 stop ND filter to throw in my bag and experiment with. I understand that the B & W filters & cokin z filters are well thought of but the daddy of them all is the lee big stopper. The problem with the screw in filters is that its dark to compose your scene where as with the drop in type you can compose normally then drop in the filter. I have a passable knowledge of curves and colour theory and think I should be able to correct a slight colour cast (as long as its consistent) Is t worth buying a cheaper filter to see how I get on...or will i end up buying twice? Are Lee filters worth the money or would something cheaper suit my needs. Any recommendations?