Originally posted by JRock What are the benefits of sky and haze filters?
Haze filters have a slight yellow cast (to counteract the bluish cast caused by haze).
Skylight filters have a slight pink cast (for a warming effect in order to reduce overly dark blue skies)
UV filters are neutral in the visible colour range. The other two above often reduce UV as well.
None of these are required for digital cameras really. You can achieve the effect of the first two with PP and digital sensor are much less sensitive to UV than film is.
Many (myself included) use UV filters for protection. But, you can get pure protection filters (without a UV filter function) as well. I suggest to buy premium multi-coated filters only.