I’m often asked whether I use filters, and which kind.
When I was shooting film, I maintained an entire stack of color correcting filters which I used according to the number of mireds of correction needed (micro reciprocal degrees), according to my Gossen Color Pro 3f color meter. With digital, I don’t bother to color correct via filters, except under extreme conditions, like the high mountains before dawn, because my research showed that it was not necessary.
Setting aside specialty filters (eg infrared), there are really only two types of filters I use today, and that’s because they can reduce image quality, especially if not kept spotless. See Do Filters Reduce Image Quality. Especially with top-end glass, filters are pointless in most cases except for protection, and a lens hood offers most of that.
I do use a neutral UV filter to protect the lens from blowing dust/dirt in desert areas, salt spray near the ocean, or any similar conditions. I’ve measured a variety of filters for neutrality, and some brands are simply not neutral, which means they are attenuating some part of the spectrum— no thanks. But I’ve measured the B+W filters and found them to be neutral, so I stick with those.
The other filter I’ll use is a polarizer, though I use one infrequently, because the effect often looks too much like an over-saturated postcard; I tire of that look rather quickly. But when it comes to a polarizer, the B+W Kaesseman (edge sealed) version is what I prefer— it’s a long-term investment.
I avoid anything but brass-ring filters and anti-scratch multi coated filters: to keep it consistent I have standardized on the B+W MRC line (multi resistant coating).
See my wish list of B+W filters in sizes from 52mm to 82mm.