Currently I shoot 99% of the time w/ a Panny 20mm which has a Hoya HMC Haze UV(C) Filter: Amazon.com: Hoya HMC Haze UV(C) - Filter - UV - 46 mm: Camera & Photo I plan to p/u the Olympus 45mm 1.8 ASAP and use that as well... My questions are these- 1. What filters are recommended to own that stay permanently attached on the lens? 2. What filters should I use (need) for bright outdoor shots? 3. For the ND filters, does it make sense to purchase them for the 46mm Diameter of the Panny & use a step down ring for the times I'll need it for the Kit lens / Oly 45mm (37mm Diameter)? 4. Is the Hoya currently on the Panny a good filter to keep on all the time? I am not looking to spend anything crazy, but am open to all suggestions and knowledge... Thanks again in advance!