I am just switching into digital photography with a new DSLR. I have had SLRs before and only bought "basic" filters. I don't know if this is relatively new or what --- but I did not realize there is such a wide range of UV filters available. My lens is 77mm. I wish to get a UV filter first to protect the lens. Here are my questions: 1. Any advice on makers/brands? Tiffen? B+W? Hoya? Hassleblad? 2. What do I look for? Multi-layer? UV + IR? 3. Will the filter reduce the amount of light into the camera? Some expensive ones advertise that they do not -- but do the less expensive filters actually reduce f-stop? Thanks to all!