Filters are a film relic. You don't need them these days.
The cut down the amount of light getting into the camera which when in most cases light is at a premium anyway isnt good. You're going to get longer shutter speeds, less control over DoF or ISO noise problems as a result.
Most modern digital cameras do manual white balance which completely removes the need for a filter. The really good ones do RAW (or can be hacked to do RAW) which removes the need even for manual WB.
Filters are also "calibrated" for a specific depth in specific conditions. Go deeper, shallower, cloudy day, in shade etc and they quickl start to tint the picture.
My advice - don't bother.
The cut down the amount of light getting into the camera which when in most cases light is at a premium anyway isnt good. You're going to get longer shutter speeds, less control over DoF or ISO noise problems as a result.
Most modern digital cameras do manual white balance which completely removes the need for a filter. The really good ones do RAW (or can be hacked to do RAW) which removes the need even for manual WB.
Filters are also "calibrated" for a specific depth in specific conditions. Go deeper, shallower, cloudy day, in shade etc and they quickl start to tint the picture.
My advice - don't bother.
