CharlieX90 wrote:How do the filters help with sunny days or water scenes? Just curios as i thought about getting a filter.
Charlie,
UV filters won't do anything at all in digital photography. It won't cut glare and it won't affect image quality, as UV light affects a digital sensor in no way whatsoever. So to me, it's just putting an extra piece of glass in between subject and sensor.
Neutral density and circular polarizing filters are sometimes useful. Headlight glare, however, is best avoided by not shooting that steep into a locomotive's headlight, however, as we all know, sometimes it's unavoidable. So, if you cut the stops of light of your photo coming from the headlight, you could conceivably reduce the glare. CP filters, ND filters, and graduated ND filters all have their places. I know a lot of guys who use CP filters for water glare, but no experience with headlight glare (could be similar).
A great example for me to use an ND filter was track and field. I wanted to do a pan shot where the athlete's head was stationary, but the legs and arms were in a blurring/running motion. The f/2.8 lens I was using I had set to 1/80s, zoomed out to 200mm I could only close down to f/8. At ISO 100, I was still way overexposed. So with a 2-stop ND filter, I could now shoot the scene at f/8, 1/80s, ISO 100, and be properly exposed, whereas nothing else I could have done would have achieved the same result. Slower than 1/80s this type of shot won't work either, so that truly was the only option.
I'm sorry I don't have more experience in glare, but those are the 3 you would choose from if you did choose a filter.