I'm looking to purchase a graduated neutral density filter (will consider both the Tiffen digital series as well as a square filter with a Cokin A or P-series mount). I am also looking for a line of neutral density filters. * Cokin P-series mount with 58mm adapter * HiTech/Tiffen square GND filters (varying strengths and hard/soft) * Tiffen Digital HT 0.6x (circular screw-in) * 58mm ND filters of various strengths * 58mm linear polarizer (yes, going to try to make a variable ND out of this) I have a strong preference for slim filters if possible. I realize filters aren't that expensive, but if some of you have filters that are in good condition that you find you don't use, I'm happy to buy them off of you provided the price is reasonable. The last time I listed a WTB, I was getting offers for used lenses that were higher than what I could get by walking down the street to buy a new lens from Adorama.